bluuebunny/crossref_metadata_2025 huggingface dataset:
On the biology ofLioadalia flavomaculara(Deg.) (Col., Coccineffidae), a predator of the wheat aphid (Schizaphis graminum(Rond.)) in South Africa
Authors: Brown H. Dick
Published: July 2009

An account is given of the biology and different life stages ofLioadalia flavomaculata(Deg.), an important predator of the wheat aphid,Schizaphis graminum(Rond.), in the Orange Free State, South Africa. Eggs are laid in batches of 6–23 eggs, generally on the soil, and incubation takes 2.1–2.8 days at 32°C and 8.6–9.1 days at 16°C. There are four larval instars, the last of which has the longest duration; total development of the immature stages averaged 11.5, 161, 220, 30.2, 35.5 and 54.0 days at 32, 27, 24, 21, 18.5 and 16°C, respectively. Beetles mate within a few days of emergence and oviposition commences 3–10 days later, depending on temperature. Maximum fecundity averaged 858.5 eggs at 24°C. From 20.7 to 24.6 eggs per day were laid at the higher range of temperatures studied (24–32°C). Oviposition took place mainly during the day. Adult life span was 24–74.3 days.
On the biology of the immature stages of the almond wasp, Eurytoma amygdali End. (Hym. Eurytomidae) in Israel
Authors: Plaut H. N.
Published: July 2009

The distribution of the almond wasp, Eurytoma amygdali End., as a major pest of almonds in areas of the eastern Mediterranean, a general outline of its seasonal history, and studies on the biology of the adult in Israel, have been reported previously (Plaut, 1971a). This paper presents data obtained in 1964–71 on the biology of the immature stages.
A revision of the north-western European species of thelaevigatus-group ofApantelesFörster (Hymenoptera, Braconidae)
Authors: Nixon G. E. J.
Published: July 2009

The north-western European species of thelaevigatus-group ofApantelesare revised. Forty species are dealt with, of which twenty are described as new. Brief notes are added on North American species of the group in the British Museum (Nat. Hist.) to assist their eventual correlation with the European species.
The ant mosaic in Ghana cocoa farms
Authors: Majer J. D.
Published: July 2009

The distribution of ants in a 2·25-ha cocoa plantation at the University of Ghana Agricultural Research Station, Kade, was recorded in December 1970. The 44 species of ants found could be grouped as dominant, co-dominant, sub-dominant and nondominant. Oecophylla longinoda (Latr.) and Macromischoides aculeatus (Mayr) were mutually exclusive as were six Crematogaster spp.; the latter were also exclusive of O. longinoda and M. aculeatus. Camponotus acvapimensis Mayr became dominant under insolated conditions, and Platythyrea frontalis Emery for reasons unknown. The distribution of these ant species in cocoa plantations resembles a three-dimensional mosaic which is preserved by their aggressiveness and by competition for food and nesting sites. It is suggested that this mosaic is due to vegetative succession.
Studies on the ecology of Aphis craccivora Koch (Hem., Aphididae), the vector of rosette disease of groundnuts, in Uganda
Authors: Davies J. C.
Published: July 2009

Observations on Aphis craccivora Koch at Serere, Uganda, in 1964–68 showed that dry season carry-over of aphids could occur on the common weeds Euphorbia hirta and E. prostrata; at other times aphids were seen on Gliricidia sepium, Cassia tora, Centrosema pubescens and Macroptilium atropurpureum, the last two being increasingly used as pasture legumes. In pot tests, attempts to transfer the virus through G. sepium, Cassia tora, Stylosanthes guianensis and Centrosema pubescens were unsuccessful. Volunteer groundnuts growing in open situations were an important source of virus and vector. Field studies on menazon-sprayed and unsprayed plants closely or widely spaced showed that aphid numbers increased rapidly on the groundnut crop 31–45 days from emergence but declined rapidly as the plants matured. Superficially the plants appeared to be free of aphids but large populations were often found on hypanthia, flowers and gynophores. Coccinellids, especially Cheilomenes sulphurea (Ol), were important predators. Aphid numbers were far higher on groundnuts with low plant densities, possibly because the number of favoured feeding sites is increased, but the number of plants infested was not significantly different at high and low densities. Yellow panels had little effect on aphid numbers. Spraying with menazon (294 g active ingredient/ha, 5 times) prevented breeding by incoming alates.
Field studies of Glossina morsitans Westw. (Dipt., Glossinidae) in relation to Rhodesian sleeping sickness in N'gamiland, Botswana
Authors: Lambrecht Frank L.
Published: July 2009

Epidemiological studies of Rhodesian sleeping sickness and its vector Glossina morsitans Westw. were made near Motsowi in the western floodplains of the Okovango Swamps, Botswana, during 1967–68. The low apparent densities of the fly (12–27 in three fly rounds compared with 124 in a fourth located in a more densely forested area to the east) and low recapture rates (1·3–3·9%) indicated the Motsowi area to be a feeding ground. Peak densities in January and troughs in October reflected seasonal movements of the fly to and from their dry-season retreats to the east. Most bloodmeals (61%) were on warthog, but 5·5% were on reedbuck in which the Trypanosoma brucei infection rate was 33%. In the Motsowi area the total trypanosome infection rate in G. morsitans was 5·7%,, with T. brucei 0·6%, but the rate varied between localities elsewhere in the Okovango. Man's movements into the fly areas to the east offer the main pathway for transmission of T. brucei, perhaps aided by seasonal movements of reedbuck closer to the settlements. The incidence of human trypanosomiasis is therefore unlikely to be reduced by insecticide campaigns in the farming areas, but livestock will benefit from a reduction in cattle trypanosomiasis.
A critical chromosome analysis of Glossina austeni Newst. (Dipt., Glossinidae)
Authors: Southern D. I. , Craig-Cameron T. A. , Pell P. E.
Published: July 2009

The diploid chromosome number of G. austeni Newst. from the Langford colony is 2n = 14 ± 2, + XX/XY. Chromosomes have been karyotyped and include a pair of large submetacentrics (L1), a pair of shorter metacentrics (L2) and a group of small telocentries (S). The X and Y elements constitute a heteromorphic pair. The S chromosomes together with the Y element display allocyclic behaviour during nuclear division. Pre-meiotic RNA synthesis has been followed by autoradiography, and differential staining of DNA with quinacrine dihydrochloride by fluorescence microscopy.
Some evidence of gustatory discrimination in the cotton stainer Dysdercus fasciatus Sign. (Hem., Pyrrhocoridae)
Authors: Peregrine D. J.
Published: July 2009

In laboratory experiments with Dysdercus fasciatus Sign, systematic testing of the stylets with a sucrose solution and distilled water has shown that the receptors mediating the salivary response to sucrose are located either on the maxillary stylets or at some site internal to them. Electronmicroscopical examination showed that the maxillary stylets were not innervated, and histological evidence further suggested the epipharyngeal organ as the site of gustatory discrimination. Dendrites located in the mandibular sclerites by means of the electron microscope could possibly have a proprioceptor function.
A laboratory study of the effects of some soil-applied organophosphorus pesticides on Carabidae (Coleoptera)
Authors: Critchley B. R.
Published: July 2009

Time/mortality studies with Carabidae exposed to thionazin, phorate, disulfoton and menazon in an acid sandy loam soil were done in controlled laboratory conditions. Carabids were killed by soil treated with thionazin within dosage rates normally required for satisfactory control of nematode or insect pests of crops, i.e., 2·24–8·96 kg/ha, but menazon was virtually non-toxic. Soil moisture increased the speed of kill of Carabidae in thionazin-treated soil presumably by affecting processes of adsorption and desorption of the pesticide to soil colloids and by influencing burrowing behaviour. The speed of kill increased with a rise in temperature, mortalities occurring 2·2 × faster at 10°C, 8·1 × faster at 15°C and 11·8 × faster at 22°C than at 7°C, but was decreased by illumination which decreased the activity of the nocturnal Carabids. The addition of calcium carbonate to increase soil pH did not alter immediate mortality by thionazin but persistence was decreased. Speed of kill was negatively correlated with adult size of Carabid species that behaved similarly, small species such as Bembidion lampros (Hbst.) (mean weight 2·1–2·2 mg) dying 12–13 × faster than female adults of Pterostichus vulgaris (L.) (mean weight 195 mg). Species which burrowed in soil were more susceptible than those which did not, as were newly moulted or starved adults. At 15°C and in wet conditions the “ half-life ” of thionazin based on speed of kill in a soil of pH 6·1–6·7 was 1–2 weeks but when determined by gas-liquid chromatography was 3–4 weeks at 22°C. Leaching could account for the loss of up to 12% of thionazin from the top 9 cm of soil.
Notes on the classification of the tribe Scolytini (Coleoptera, Scolytidae)
Authors: Wood Stephen L.
Published: July 2009

Following an evaluation of the anatomical characters and habits of the Scolytini, four genera are recognised, namely Scolytus Geoffroy, Scolytopsis Blandford, Camptocerus Dejean, and Cnemonyx Eichhoff (=Loganius Chapuis, Ceratolepis Chapuis, Coptosomus Schedl, syn. n.). Two South American species, Camptocerus aquilus and C. rectus, having an ambrosial habit, are described as new.
Biological studies of Brazilian Scolytidae and Platypodidae (Coleoptera). I. Camptocerus Dejean
Authors: Beaver R. A.
Published: July 2009

Observations were made on Camptocerus aeneipennis (F.), C. aterrimus Eggers, C. niger (F.) and C. aquilus Wood infesting felled trees in the gallery and valley forests of the north-eastern Mato Grosso between September and December, 1968. The lifecycles of all four species are completed in 7–10 weeks. The gallery systems resemble those of the Xyloterini and Scolytoplatypus. The maternal galleries penetrate the wood and either lie in the transverse plane or run longitudinally, depending on the stem diameter. Trees of the family Burseraceae are especially attacked. The larvae are mycetophagous, developing in cradles which they enlarge as they grow. Larvae were attacked by an ectoparasitic Braconid wasp and predatory beetle larvae. Larval mortality is lower when one or both parents remain in the gallery. The potential forest importance of the four species could be contained by bark removal and rapid drying.
The visual responsiveness of the tsetse flyGlossina morsitansWestw. (Glossinidae) to moving objects: the effects of hunger, sex, host odour and stimulus characteristics
Authors: Brady John
Published: July 2009

The responses of adultGlossina morsitansWestw. to large slowly moving visual stimuli were tested in the laboratory. The standard stimulus, lasting 60 s, consisted of a vertical black stripe (5° wide) on a white background moved 12 times past a window (25° wide) at 13·5°/s. The kinetic responses (take-off), but not orientation towards the stripe, went through a daily cycle with morning and evening maxima some 500% greater than the mid-day response. Kinetic responsiveness in both sexes and all ages of fly increased in an overall linear manner during five days' starvation, though pregnant females were about half as responsive as mature males. The intensity of orientation also increased with starvation, at least in males. For take-off, the minimum stripe width eliciting responses subtended ca 0·6° to the flies, and the optimum angular velocity was 3–7°/s, for orientation, 2–20°/s; the distance of the stripe appeared unimportant. Human odour elicited take-offs in the absence of the visual stimulus, and enhanced the visual responses if these were tested within three minutes of the start of odour stimulation; these effects were much greater in teneral than in mature males. It is concluded that the differences between the sexes and physiological stages of fly are mainly quantitative, and that the accepted view of four physiologically distinguishable phases of behaviour is therefore unsatisfactory. Instead, it is proposed that tsetse behaviour is the outcome of continuously variable responsiveness to visual host stimuli, and not a succession of behavioural entities.
The inheritance of life-cycle differences in Myzus persicae (Sulz.) (Hem., Aphididae)
Authors: Blackman R. L.
Published: July 2009

The response to short photoperiod (10 h) of the F1 and F2 sexual generations of Myzus persicae (Sulz.) resulting from a cross between oviparae from a holocyclic clone and males from an androcyclic clone were examined and compared in experiments done at Imperial College Field Station, England. F1 and F2 progeny segregated into three distinct phenotypes; holocyclic, androcyclic and intermediate. Intermediate clones reared at 10 h photoperiod produced alatae which were physiologically intermediate between gynoparae and virginoparae, because their progeny consisted of oviparae, apterous virginoparae and intermorphs. Intermediacy was not affected by temperature and seems to be genetically determined. Segregation ratios in the F1 and F2 indicate that the androcyclic condition is induced by a recessive ‘ switch-gene ’ which completely suppresses the production of sexual females, and partially suppresses male production. This gene could be present in the heterozygous condition in a large proportion of parthenogenetic lines of the aphid, and thus confer a latent potentiality for anholocycly on populations even where conditions will not regularly permit this method of overwintering. Conversely where anholocycly is strongly favoured many aphids would be homozygous for the recessive, androcyclic character, but the potential for gamic reproduction could remain widespread.
New Genera and species of Cicadelloidea (Homoptera, Auchenorrhyncha) from economic Plants in India
Authors: Ghauri M. S. K.
Published: July 2009

Following examination of Cicadelloidea off potato, castor, millets and berseem from Simla, India, and of some of Distant's type specimens, the genera Jilinga, Pseudosubhimalus and Sarejuia are described as new, and new combinations and synonymies given ; two new species are also described under Aconurella Ribaut and Sarejuia. Dio Distant, Erythridea Ribaut and Erythria Fieber are considered to be distinct, and a key to these genera is given.
The emission and form of spermatophores and the fine structure of adultEriophyes sheldoniEwing (Acarina, Eriophyoidea)
Authors: Sternlicht M. , Griffiths D. A.
Published: July 2009

The emission and form of the spermatophores ofEriophyes sheldoniEwing are described and illustrated. Glued to the substratum by a drop-like pad which varies in shape, they consist of a stalk with a basal stiff section and a distal flexible part ending in a strongly convex lens-like head, in which the sperm mass is kept. The fine structures of the adult integument, characteristic of this species, are described and illustrated.
Effect of diazinon selection upon two organophosphorus-resistant field strains of Lutilia Cuprina (Wied.) (Diptera, Calliphoridae)
Authors: Shanahan G. J. , Roxburgh N. A.
Published: July 2009

Two field strains of Lucilia cuprina (Wied.) of different susceptibilities to diazinon were selected over 25 generations by immersion of first-instar larvae in aqueous emulsions of diazinon for five minutes ; the resistance of the larvae and adult females was compared with a standard laboratory susceptible strain. Resistance increased rapidly in both strains, reaching a maximum for adult females (R.F. = 5–6) in generation 3 and for larvae (R.F. = 46–60) in generation 6. After removal of selection pressure at generation 8 the resistance factor fell to 20–24 by generation 25. Because the resistance mechanisms are known to place their carriers at a disadvantage in the absence of selection pressure, the practical implications of the rapid increase in resistance must await results of experiments with known genotypes.
Systematic studies on Eulophidae of economic significance (Hymenoptera, Chalcidoidea)
Authors: Kerrich G. J.
Published: July 2009

Achrysocharis diplosidis reared from galls of the Cecidomyiid Hyperdiplosis eupatorii Felt in Trinidad and Brazil is described, A. pulcherrima Kerrich is recorded from Pakistan, and a key separating these two gall-associated species of Achrysocharis Girault is given. Larval or pupal parasites of Promecotheca cumingii Baly (Hispidae) in Sri Lanka are described as Cotterellia lankensis, and of Promecotheca spp. in New Britain, Admiralty Is. and New Guinea Territory as C. insularis; C. podagrica Waterston is redescribed, and a key is given to the three species of Cotterellia Waterston ; the generic relatives of Cotterellia are discussed and a key separating this genus from Platocharis Kerrich and Schizocharis Kerrich is given. Rekabia Cameron is placed in synonymy with Euplectrus Westwood, and notes are given on material for a classification of the relatives of Stenomesius Westwood.
The distribution and life-history of Milionia isodoxa Prout (Lepidoptera, Geometridae), a Pest of planted hoop pine in papua New Guinea
Authors: Wylie F. R.
Published: July 2009

Milionia isodoxa Prout is a serious defoliator of planted hoop pine, Araucaria cunninghamii, in the Highlands of Papua New Guinea. The insect has been found in seven mainland districts, and larvae have been collected from naturally occurring hoop pine in the Madang and Southern Highlands Districts. M. isodoxa is multivoltine, the life-cycle taking approximately eight weeks. The durations of the five larval instars are 4, 4, 4, 5 and 10 days, respectively, and of the pupal period approximately two weeks. The males feed primarily on organic solutes, the females on nectar, so that the sex ratio of adult M. isodoxa in the hoop pine plantations at Bulolo varies with the time of day and locality. Pupae may be attacked by two species of Ichneumonidae and one of Braconidae, and the ants Anoplolepis longipes (Jerd.) and Oecophylla smaragdina (F.) are particularly effective larval predators in the Bulolo plantations; some adults are killed by spiders. The fungus Beauveria bassiana is responsible for high pupal mortality in the Highlands. Frass-drop frequency studies of M. isodoxa larvae in the laboratory showed that feeding activity is greatest in the early instars, and is greater at night for all instars. Larvae reared at 21°C required 14 days more for development than did those reared under the normal daily fluctuation, 19–31°C.
The Anopheles barbirostris group (Diptera, Culicidae)
Authors: Reid J. A.
Published: July 2009

The group of Anopheles barbirostris Wulp is shown to consist of some 11 closely similar species, five of which are described as new. Keys for identification are provided. The group is divisible into two parts, the subgroups of A. barbirostris and A. vanus Wlk.

Two (or possibly three) species in the barbirostris subgroup are disease vectors.

A. barbirostris sensu stricto is the commonest and most variable species of the group and has the widest range, occurring probably from India to the Moluccas excluding only Borneo and the Philippines. Larvae can be found in a variety of breeding places in still or slowly moving water. Throughout its range, except perhaps in the Celebes, it appears to be largely zoophilous and not a vector of disease.

A. campestris sp.n. is very closely related to barbirostris. It appears to be confined to the alluvial plains of coasts and deltas, and may be limited to the mainland of Asia. It is common on the west coast of the Malay Peninsula where it is anthropophilous and an important vector of human (and possibly also simian) malaria, and of filariasis due to the periodic form of Brugia malayi. It is probably at least a minor vector of malaria and filariasis in the plains of Thailand.

A. donaldi sp.n. is the principal member of the group in Borneo, and is locally common in Malaya where the larvae are usually found in more shaded places than those of barbirostris. In Borneo it is a minor vector of malaria and filariasis, and possibly in Malaya also.

A. franciscoi sp.n. is the Philippine representative of the barbirostris subgroup.

A. hodgkini sp.n. is widespread (Thailand, Indo-China, Malaya and Borneo), but seldom common. It is a species of the forest and forest edge.

A. pollicaris sp.n. is an uncommon but easily recognised forest species only known at present from Malaya.

The vanus subgroup consists for the most part of uncommon species having little contact with man and usually associated with forest. A. vanus sensu stricto occurs in the Celebes and Moluccas where it is common, and also in Borneo and the Philippines; A. barbumbrosus Strickl. & Chowd., replaces vanus in the western half of the archipelago and on the mainland; A. ahomi Chowd., is known from Assam; A. manalangi Mendoza is confined to the Philippines; finally there is an unnamed species in Ceylon with speckled legs which was previously identified wrongly as A. pseudobarbirostris Ludl.
Possible effects of the application of malathion on the small moth borer, Diatraea saccharalis (F.), and its parasite Lixophaga diatraeae (Tns.) in Jamaica
Authors: Manser P. D. , Bennett F. D.
Published: July 2009

Investigations were undertaken in Jamaica to determine whether or not the application of malathion for the control of the West Indian cane-fly, Saccharo-sydne saccharivora (Westw.), disturbed the natural control exerted by Lixophaga diatraeae (Tns.) on its host Diatraea saccharalis (F.). It was demonstrated, by exposing caged adults of Lixophaga, that adults present in the field at the time of insecticidal application would be killed but because of the short residual action of malathion the reduction in the parasite population would only be temporary. A comparison of the degree of parasitism in sprayed and unsprayed fields did not reveal any evidence of reduction in the rate of parasitism. The extent of damage by Diatraea in sprayed fields was significantly less than in unsprayed ones and factors which might account for this are discussed.
Hofmannophila pseudospretella(Stnt.) (Lep., Oecophoridae), its status as a pest of woollen textiles, its laboratory culture and susceptibility to mothproofers
Authors: Cole J. H.
Published: July 2009

Hofmannophila pseudospretella(Stnt.) is a very widespread and common omnivorous scavenger in Britain. It is able to digest keratin and, while rarely occurring in large infestations, has a nuisance value as a textile pest in dwellings. It is commonly found breeding in birds' nests and dry organic débris likely to be found in attics and roof spaces, and mature larvae wandering from the feeding site are probably the only cause of damage to domestic textiles which, according to our records, are principally carpets.

A method of maintaining cultures in the laboratory and obtaining standardised larvae for mothproofing tests is described.

Adequate protection against newly hatched larvae was given by 0·1 per cent. Dielmoth (25 per cent, dieldrin) and 1·0 per cent. Mitin FF (an unknown percentage of N-(3,4-dichlorophenyl)-N′-2-(2-sulpho-4-chlorophenoxy)-5-chlorophenyl urea, sodium salt), while six-week-old larvae were not controlled by 0·15 per cent. Dielmoth or 1·0 per cent. Mitin FF. No protection against larvae in the wandering stage was given by Dielmoth in concentrations up to 0·63 per cent, or by 1·0 per cent. Mitin FF.

Both six-week-old and wandering larvae were controlled by 5·0 per cent. Mystox B (20 per cent, pentachlorophenol) and the latter also by 4·0 per cent. Mystox LPL (100 per cent, commercial pentachlorophenyl laurate).
A hand-operated suction apparatus for the extraction of arthropods from grassland and similar habitats, with notes on other models
Authors: Southwood T. R. E. , Pleasance H. J.
Published: July 2009

Earlier types of suction sampling apparatus, driven by electric or petrol motors, are briefly reviewed and their disadvantages for work in remote areas indicated. To overcome these a cheap, simple, hand-operated model has been developed and the construction of this is described. However, unlike some of the motorised models, it does not extract all the fauna from the area sampled.
The evaluation of insecticides as soil and mound poisons against termites in agriculture and forestry in West Africa
Authors: Sands W. A.
Published: July 2009

The termites most injurious to crops and trees in West Africa are subterranean or mound-building species of the Termitidae, mainly Macrotermitinae with some Amitermitinae and Nasutitermitinae. Insecticides for their control may be applied generally to the soil, locally around the plant or directly to the colony.

In investigations in Northern Nigeria, dusts containing aldrin or dieldrin were mixed with the top six inches of soil of a type commonly cultivated (a slightly humic, brown, loamy sand), exposed to weathering in the field and tested for persistence of the insecticides by bioassay at intervals, using workers of Trinervitermes ebenerianus Sjöst., a locally common surface-foraging species. The concentration of the insecticide in the soil was measured in terms of the time in days taken for 50 per cent. of the insects to be killed (T50). After 33–34 months, between one-third and one-fifth of the insecticide remained in soil originally treated with 0·5, 2 and 5 lb. active ingredient (a.i.) per acre.

T. ebenerianus proved very sensitive to dieldrin; the T50 value was 1·48–4·10 days for single samples, from each of five colonies, exposed to filter paper containing 0·0018 parts per million, as compared with 10–24 days for the controls. It is suggested that general soil treatments should be used with caution until more is known of their effects on termite populations, which are important in facilitating aeration, and penetration of water, in tropical soils.

Application of dieldrin emulsion, at a dose equivalent to 1 lb. a.i. divided among the planting holes for one acre (1,225), during planting of one-year-old, root-pruned seedlings of Eucalyptus camalduensis, resulted in a mean survival after 2½ years of 60 per cent. of the young trees, as compared with 17 per cent. in untreated controls. Pot-grown seedlings of Eucalyptus spp. were similarly treated at 8 oz. a.i. dieldrin per 700 pots prior to setting out in the field, when they showed very low mortality due to termites over the next 1½ years, attack only occurring where too short a pot allowed access by Macrotermes natalensis (Hav.) to the tap root. Four hundred pot-grown cacao seedlings similarly treated with 4 oz. a.i. dieldrin showed only four deaths due to termites one year after planting out. Pre-treatment of potting soil for Eucalyptus seedlings at 5–10 oz. of 2 per cent, dieldrin dust per cubic yard (sufficient for 500 pots) has given promising preliminary results.

Colonies of M. natalensis, which constructs large mounds, were successfully poisoned with 2½ fl. oz. of aldrin 40 per cent, emulsifiable concentrate in six gallons of water applied through three auger holes made into the central ‘ hive ’, containing the queen cell and associated chambers. It is considered that this dose could safely be reduced.
Notes on parasites of Pentatomidae and Scutelleridae (Hemiptera-Heteroptera) in Middle East countries, with observations on biological control
Authors: Brown E. S.
Published: July 2009

A number of observations were made on parasites of certain Pentatomoids (sunn pest) attacking wheat in Middle East countries, during the course of other work on these pests. The principal host species studied were Eurygaster integriceps Put., E. maura (L.) and Aelia rostrata Boh. The data concern both Dipterous (Tachinid) endoparasites of the adult bugs, and also Hymenopterous (Scelionid) egg-parasites; the observations were made principally in central Turkey, and in the Varamine district of Iran. A few observations on predators were made also.

The data concerning Tachinids consist of host records for six species of parasites. In no case observed by the author did these parasites appear to be of great importance in reducing the numbers of sunn pest; the same is true of the few instances of predators recorded.

Observations were made on six species of Scelionid egg-parasites (five species of Asolcus and one of Hadronotus), five of which were bred from eggs of four species of Pentatomoid hosts collected in the field. The species concerning which the most comprehensive data were obtained were Asolcus rufiventris (Mayr), A. semistriatus (Nees) and A. vassilievi (Mayr). Egg-parasites are well known to be more efficacious in reducing sunn-pest populations, and A. semistriatus has been extensively used in Iran as a biological control agent. The data obtained enabled some ideas which are of importance for the use of egg-parasites in biological control to be formed and discussed. These concern principally (a) the susceptibilities of different hosts to parasitisation; (b) host selection by parasites; (c) the selection of a species of parasite most suitable for biological control in a particular area.
Control of Aleuroglyphus ovatus (Troupeau) in flea cultures
Authors: Sternberg S. , Tahori A. S.
Published: July 2009

In tests of acaricides for the control of a Tyroglyphid mite, Aleuroglyphus ovatus (Troupeau), infesting cultures of the oriental rat flea, Xenopsylla cheopis (Roths.), in jars provided with linen covers and containing Purina dog food in sand as the rearing medium, Tedion and Kelthane proved ineffective, but light infestations (100 cc. of medium inoculated with 500 mites) were satisfactorily controlled by chlorobenzilate at 0·2 p.p.m. in the rearing medium or as a 0·05 per cent, solution in acetone painted on to the inner wall of the jar and used to soak the linen cover for three seconds. Heavy infestations (100 cc. medium inoculated with 2,000–3,000 mites) were controlled by chlorobenzilate at 20 p.p.m. in the medium or as a 0·5 per cent, solution applied to both the linen cover and the inner rim of the jar; a combination of both treatments (using 2 p.p.m. and a 0·5 per cent, solution) gave adequate control for 30 days.

The flea larvae were unaffected by 2 p.p.m. chlorobenzilate in the rearing medium; 20 p.p.m. killed larvae, but not adults. Neither stage was affected by treating the linen cover and inner rim of the breeding jar with a 0·5 per cent, solution of chlorobenzilate.

Measures are recommended for maintaining flea cultures free from mites, based on these experimental results and on a year's practice.
The susceptibility of tsetse flies to topical applications of insecticides. III.—The effects of age and pregnancy on the susceptibility of adults of Glossina morsitans Westw
Authors: Burnett G. F.
Published: July 2009

Solutions of dieldrin, γ BHC, p, p′DDT and Baytex were applied topically to pregnant females of Glossina morsitans Westw. and also, in most cases, to fertilised flies over 21 days old and not noticeably pregnant, to virgin flies over 21 days old, and to males over 18 days old. Pregnant flies required about nine times as much dieldrin as young flies for comparable mortalities, and non-pregnant fertilised flies about four times as much. It was not possible to determine proper regression lines for other insecticides and classes of flies but significant increases in tolerance, as compared with that of young flies, were shown by pregnant flies to γ BHC and DDT, by old virgins to dieldrin and DDT but not γ BHC, and by fertilised flies to γ BHC and DDT. Pregnant flies and virgins showed no increased tolerance to Baytex, and old males showed none to dieldrin, γ BHC or DDT.

These results are discussed in relation to aerial spraying of tsetse habitats and it is suggested that they explain some unexpected past results.
The susceptibility of tsetse flies to topical applications of insecticides. IV.—Wild-caught adults of Glossina swynnertoni Aust.
Authors: Burnett G. F.
Published: July 2009

Dieldrin, γ BHC, DDT, Telodrin and Baytex have been applied topically in oil solutions to G. swynnertoni Aust. caught as wild adults. The order of toxicity of these compounds was the same as that to laboratory-emerged G. morsitans Westw. and all were relatively more effective. Wild females were 2–3 times as tolerant of the chlorinated hydrocarbons as the males, and pregnant females required nine times as much DDT as the males. Greater tolerance to Baytex did not exceed the difference in body weights between the sexes. These results confirm those obtained with G. morsitans and are attributed to the increased tolerance to chlorinated-hydrocarbon insecticides shown by females as they age and become fertilised and pregnant.

There is no such increase in tolerance of females to Baytex and the importance of this in planning practical control measures is indicated.
The pregnancy rate in Glossina palpalis (R.-D.) in southern Nigeria
Authors: Jordan A. M.
Published: July 2009

Females of Glossina palpalis (R.-D.) were dissected and examined for pregnancy at the Ugbobigha field station of the West African Institute for Trypanosomiasis Research in southern Nigeria between January 1958 and October 1959. Of 2,490 females dissected, 46 (2%) were virgin; 764 (31%) had an egg in utero and 221 (9%) a larva in utero. Highest pregnancy rates were found in months with heaviest rainfall and lowest mean temperature, saturation deficit and evaporation rate.

The pregnancy rate in G. palpalis near Kaduna, in Northern Nigeria, was nearly twice that found at Ugbobigha, the major difference being in the number of females with a larva in utero. It is suggested that in the Ugbobigha area an adverse factor operates in the late egg or early larval stage, causing abortion; this is probably not a direct effect of climate or of insufficient food but may partly be related to the possible inability of females to obtain a blood-meal at just the right stage in gestation. Low pregnancy rates may, at least in part, explain the low densities of G. palpalis commonly found in the forest belt of West Africa, despite the wide distribution of the species in such areas.
The productivity of grasslands in England for Oscinella frit (L.) (Chloropidae) and other stem-boring Diptera
Authors: Southwood T. R. E. , Jepson W. F.
Published: July 2009

Dissections of over 93,000 grass stems obtained by random core-sampling of natural grasslands at a site in Berkshire largely confirm earlier conclusions regarding the associations of different species of dipterous stem borers and grasses. Allowing for the number of stems of each grass species per unit area, the densities of larvae were greatest in Anthoxanum odoratum, Poa and Lolium and lowest in Dactylis glomerata. Oscinella frit (L.) was less abundant than Cetema spp. and Opomyza germinationis (L.); it was not found in D. glomerata but was most abundant in Lolium and Festuca. Sampling showed that overwintering larvae of O. frit suffer at least 50 per cent, mortality between September–December and January–March.

Previous studies have largely concentrated on populations in different species of grasses, but it is advantageous to consider the production of O. frit in terms of short (grazed or regularly mown) grasslands and long grasslands (hay fields, uncut commons and rough grazing); comparisons of figures obtained by core-sampling for larvae and emergence traps for adults indicate a production from short grassland and long grassland of about 11 and under 1 overwintered adult per sq. yd., respectively. Having regard to the greater productivity of common leys, dominated by Lolium and Poa, a national average for the first figure would be 15. There is little increase from generation to generation in grassland populations during the year, in contrast with the situation in oats.

From tentative estimates of the acreages and productivities of the different sources of O. frit in England and Wales as a whole, it is clear that the majority of the adults of O. frit are produced by grasslands in the spring and summer and by the oat panicles in the autumn, the latter population being much the greater. As O. frit is a migratory insect, such a conclusion is especially significant and indicates that during the autumn the ‘ population pressure ’ in the grasslands will be very different to that during other seasons.
The status of the foreign grain beetle, Ahasverus advena (Waltl) (Col., Silvanidae), as a pest of stored products
Authors: Woodroffe G. E.
Published: July 2009

The ability of the foreign grain beetle, Ahasverus advena (Waltl), a reputed mould feeder, to breed on various foods under conditions not conducive to mould growth was investigated in a series of culturing experiments. At 25°C., on a diet of rolled oats and dried yeast, the lowest relative humidity at which successful breeding occurred was 65 per cent., although a few adults were produced at 60 per cent. R.H. Wheat germ proved a satisfactory food under these conditions and the addition of yeast or germ to cereal products enabled the species to breed in the absence of visible mould growth, which it failed to do on. the cereal products alone. Although thriving larval cultures developed with crushed, dead grain weevils (Sitophilus granarius (L.)) as food, they invariably died out without producing pupae. On oilseeds at 70 per cent. R.H., moderate breeding occurred on groundnuts, which remained free from visible mould, but little or none on copra, cocoa or palm kernels in the absence of mould.

It is concluded that most stored foodstuffs are deficient in some factor, present in adequate quantity in dried yeast or wheat germ, that A. advena requires for successful breeding and that, in the field, this requirement frequently limits the species to mouldy products, although direct damage to groundnuts at 30°C. and 70 per cent. R.H. is possible in the apparent absence of mould.
Age determination for female tsetse flies and the age compositions of samples ofGlossina pallidipesAust.,G. palpalis fuscipesNewst. andG. brevipalpisNewst.
Authors: Saunders D. S.
Published: July 2009

The age compositions of samples of females ofGlossina pallidipesAust.,G. palpalis fuscipesNewst. andG. brevipalpisNewst., are analysed by means of a method of age determination based upon the changes occurring in the reproductive system during successive gonotrophic cycles. This method of age determination is described in detail.

Females were sampled by three main methods: in traps, by catching on a bait-animal, and on a fly-round. Some flies were also found as resting flies in the undergrowth.

Trap-caught samples ofG. pallidipeswere older (i.e.), contained a larger proportion of old flies (and a smaller proportion of young flies) than the hand-caught samples. The bait-caught samples were intermediate in age structure. Correlated with the increasing mean age in the hand-caught—bait-caught—trap-caught series was an increase in the proportion of females carrying third-instar larvae and a decrease in the proportion of those carrying eggs. Results with samples ofG. palpalis fuscipesandG. brevipalpiswere not so well defined.

The results of dissecting teneral and non-teneral nullipars ofG. pallidipesandG. palpalis fuscipesindicate that females of the latter are inseminated some time before they take their first blood-meal, but teneral females ofG. pallidipesare inseminated when they come to the host to feed or after they have fed.

The relation of the ovarian method of age determination to Jackson's (1946) wing-fray categories in females ofG. pallidipes, and the probable epidemiological importance of the samples, are also discussed.
Stathmopoda auriferella(Wlk.) (Lepidoptera, Heliodinidae) infesting sorghum stored on the head in Northern Nigeria
Authors: Prevett P. F.
Published: July 2009

Stathmopoda auriferella(Wlk.) (Lepidoptera, HELIODINIDAE) is recorded as a pest in Northern Nigeria of sorghum in the field and on the head in store. Notes are given on the nature of the infestation. The mature larva is described, and characters are listed for separating it from the larvae of four common species of Lepidoptera which infest stored produce; and for separating the adult from that ofSitotroga cerealella(Ol.).
Observations on Toxorhynchites brevipalpis conradti Grünb. (Diptera, Culicidae) in Uganda
Authors: Corbet Philip S.
Published: July 2009

Observations made in Uganda on eight individuals of the mosquito Toxorhynchites brevipalpis conradti Grünb. reared in captivity from egg to adult are recorded. Larvae of this species are predatory and coexist in tree holes with those of mosquitos of medical importance.

The identification of larvae and pupae is discussed, and information provided on the following subjects: the amount of food (living larvae of Aedcs acgypti (L.)) needed for larvae to complete development; the feeding and killing behaviour of fourth-instar larvae; duration of the pupal stage; and the rate of autogenous ovarian development in the unfed female adult.

The compulsive killing behaviour shown by a fourth-instar larva about two days before it pupates could be expected to cause the death of all the other mosquito larvae in a tree hole of average size. This species is unusual among mosquitos in that pupae of females developed more rapidly than those of males.
A method of assessing the physical condition of insect-damaged grain and its application to a faunistic survey
Authors: Coombs C. W.
Published: July 2009

A method of assessing the physical condition of grain residues is described. It consists of utilising data obtained by taking the weight and volume of samples before and after sieving over a 1/10-inch mesh.

The application of this method to a survey of the insect population of wheat residues beneath the floor of a small granary in southern England is described. Information from the weight and volume data obtained enabled the samples to be classified in a manner agreeing with visual estimates. It had the advantage of objectivity.

Three vertical series of samples were taken and analysed, and the insects present counted and identified. The size, composition and distribution of the insect population is briefly discussed in relation to the condition of the residues and their depth below the surface. The fauna consisted of grain pests (Sitophilus granarius (L.), Oryzaephilus surinamensis (L.), Ptinus tectus Boield., P. fur (L.) and Hofmannophila pseudospretella (Stnt.)) and incidental species (fungus feeders and ground-dwellers) and the two groups differed in their distribution and in their apparent response to the physical conditions.
A contribution to the biology of Gryllus bimaculatus Deg. in Israel
Authors: Rivnay E. , Ziv M.
Published: July 2009

In view of the sporadic nature of outbreaks of Gryllus bimaculatus Deg., all stages of this cricket were reared in Israel at various temperatures in order to find the effect on its development and fecundity. Eggs were incubated at constant temperatures and also at fluctuating room temperatures. The mean incubation period varied from 7·5 days at 34°C. to 75 days at a mean of 16·4°C.; at 26°C., at which the percentage hatching was greatest, it was 14 days; and the threshold of development was calculated to be about 15°C. For larvae reared at constant temperatures on a diet of bread and fishmeal, the development period varied from about 32 days at 34°C. to 130 days at 22°C.; the threshold was calculated to be 19°C. For adults maintained at constant temperatures, the mean life at temperatures of 26 to 34°C. usually exceeded one month, the preoviposition period varied from 4 days at 34°C. to about 15 at 22°C., and the threshold of reproduction was calculated as 19°C. Of 16 females tested that had been reared and maintained at near optimal temperatures (30–34°C.), more than half gave rise to upwards of 500 larvae each, and two to over 3,000 each. The reproductive capacity was affected by the temperature at which the larva was reared, the number of offspring produced being greatest from pairs of adults reared at 26°, and nil from females reared at 37°C. Light-trap catches during three years showed a peak in midsummer or autumn.
The random sampling of cultures of grain weevils
Authors: Howe R. W.
Published: July 2009

Four methods have been tested of dividing cultures consisting of wheat grains containing larvae and pupae of Sitophilus granarius (L.) into samples weighing just under 10 g. and suitable for use in fumigation experiments. Two mechanical methods, each dividing a culture into two equal parts, the division being successively repeated to yield 32 samples, were shown to be satisfactory in every trial. One apparatus divided the culture on the chess-board principle, the other by means of radial fins equally spaced round the circumference of a conical divider. The standard method used at the Pest Infestation Laboratory also proved satisfactory; it consists of scooping up samples by hand radially, at random, from a culture dispersed symmetrically by pouring it over the bottom of a spherical flask, but it was evident that personal bias could be introduced by its use. The fourth method, consisting of ‘ random scooping ’, is widely used but yielded samples having considerable heterogeneity from all cultures containing larvae older than the late third instar and having a density exceeding one insect in 30 grains of wheat. This method was the only one that divided standard cultures into samples showing heterogeneity in their age structure. When cultures with an age range of only four days were divided, all four methods yielded samples for which the emergence curves were heterogeneous, apparently as a result of heating induced in samples as small as 9 g. as a result of the metabolism of the larger larvae.
Simultaneous control of three species of Glossina by the selective application of insecticide
Authors: Maclennan K. J. R. , Aitchison P. J.
Published: July 2009

An account is given of the simultaneous control of three species of tsetse fly by the selective application of insecticide to vegetation within an area of 16 sq. miles along a seasonal watercourse in Northern Nigeria constituting a permanent habitat of Glossina palpalis (R.-D.) and G. tachinoides Westw. and a hot-season concentration area of G. morsitans Westw. subsp. submorsitans Newst. The ecological zones concerned centred on small lakes fringed, in succession outwards, by open swamp, swamp woodland, swamp forest, riparian forest and riparian woodland, the whole being bounded by savannah woodland populated by G. morsitans in the wet season. All except the forest elements were subject to seasonal fires.

Against G. morsitans, insecticide was applied to the principal resting sites of flies in their hot-season concentration habitats, namely, the basal 5 ft. of shaded tree trunks over 9 in. in diameter, or 5 in. where stands were dense, in, chiefly, riparian woodland and forest. Against the other species it was applied to a height of 2½ ft. on stems, trunks and exposed roots in riparian forest and the margins of swamp forest, which were favoured as pupation sites and in which it was therefore believed that adults might rest.

A wettable-powder suspension containing 3¾ per cent. DDT was applied by pneumatic knapsack sprayer in quantities short of run-off. Temporary reduction of the strength to 2½ per cent, had no detectable effect on control.

Regular fly patrols showed an initial reduction in apparent density of G. morsitans by four-fifths, but spot checks detected a residual population that persisted up to two months in small areas. These were resprayed so as to include trunks of 5 in. diameter and branches over 3 in. in diameter at heights of 6–12 ft. The apparent density of the other species declined after treatment by over nine-tenths, in both treated and untreated zones, but following catches of a few teneral adults, indicating persistent or recurrent populations in limited areas, these were resprayed using an emulsion containing 3¾ per cent, dieldrin.

Treatment began in January 1961 and to date (April 1963) no fly has been detected since April 1961, despite repeated re-surveys. The approximate cost of labour, equipment and insecticide was £3,000; an attempt at reclamation in 1926–29 by sheer-felling over seven sq. miles, which achieved only temporary success, had cost £3,000, with recurrent annual re-slashing costs of £250, equivalent to £12,000 and £1,500, respectively, at present-day costs for labour.