bluuebunny/crossref_metadata_2025 huggingface dataset:
Chemical control of an organophosphorus-and carbamate-resistant strain of Boophilus microplus (Can.) from Queensland
Authors: Roulston W. J. , Stone B. F. , Wilson J. T. , White L. I.
Published: July 2009

Recognition in 1963 in central Queensland of the Ridgelands strain of Boophilus microplus (Can.), resistant in varying degrees in laboratory tests to all acaricides commercially available in Queensland, Australia, led to spraying trials on cattle with these acaricides to assess their effect on the resistant strain. Dosage mortality tests on larvae exposed in acaricide-impregnated filter papers, indicated the following levels of resistance, carbary 13×, carbophenothion 17×, coumaphos 1.6×, diazinon 19×, dioxathion 7.2× and ethion 2.7×.

Stalled cattle infested with either susceptible Yeerongpilly or resistant Ridgelands ticks were sprayed with the recommended concentration of commercially formulated acaricide. Efficiency of treatment was determined by comparing the number of ticks falling from sprayed and unsprayed cattle. Coumaphos (0.025%) and ethion (0.075%) produced efficient control of the resistant strain, but carbophenothion (0.086%), diazinon (0.05%) and dioxathion (0.075%) allowed considerable numbers of the resistant strain of ticks to survive. Carbaryl (0.3%) as a melt-type formulation gave inconsistent results and possible reasons are discussed. Poor control of the resistant strain was largely due to failure to kill the nymph stage.

There was general correspondence between the resisdence level determined in laboratory tests and the degree of control achieved in spraying trials. However, the reletively small difference between resistence levels of 2–3× (coumaphos and ethion) and 7× (dioxathion) was critical in the practical control of resistant ticks on cattle.

The following chemicals gave excellent control of the Ridgelands strain in spraying trials on stalled cattle: bromophos (0.15%), bromophos ethyl (0.1%), chlorfenvinphos (0.06%), chlorxylam (0.5%), Ciodrin (0.1%) Dursban (0.025%), fenchlorphos (0.2%), GS13002 (0.05%), Imidan (0.075%), methidathion (0.05%) and SD8448 (0.025%). Malathion (0.5%), prothidathion (0.075%), macarbam (0.075%) and RD12308 (0.2%) controlled the Yeerongpilly but not the Ridgelands strain. Arsenic (0.2%) produced about equal mortality in both strains, but was clearly a less efficient acaricide than organophosphorus chemicals.
Sugar-cane Moth Borers (Diatraea spp.) in British Guiana
Authors: Box Harold E.
Published: July 2009

The writer had exceptional opportunities for studying sugar-cane moth borers while engaged as entomologist to one of the most progressive cane-growing concerns in British Guiana from September 1922 until January 1925. The observations and data that follow refer to some three thousand acres of typical cultivation situated on the west bank of the Berbice River, nearly opposite the town of New Amsterdam, in which locality the borer pest probably reaches its maximum in destructiveness.
Heliothis armigera (Hb.) (Noctuidae) in Western Tanganyika. I.—Biology, with special reference to the pupal stage
Authors: Reed W.
Published: July 2009

In laboratory studies of Heliothis armigera (Hb.) in Western Tanganyika, where it may attack cotton severely, pairs of newly emerged adults, derived from sixth-instar larvae collected in the field and allowed to pupate in the laboratory, were confined separately and provided with sucrose solution. The mean number of eggs laid per female fell from 1,226 in March-May to 198 in June—July 1962. Peak egg laying occurred in the fifth to eighth nights after emergence. In April, the mean length of life of adults of either sex was about 11 days and the maximum one month. The mean incubation period of 1,436 eggs laid in March was 2·78 days, and 66 per cent. of them hatched. The mean period from hatching to pupation of 42 larvae reared on cotton squares in April was 21·1 days; each passed through six instars and required three squares in the first 14 days and a further 10 thereafter; only 22 per cent. of the dry weight of the squares was consumed and of this only nine per cent. was converted to pupal dry weight.

Pupation occurs in the soil. The mean pupal period of males increased from 16 days in March to 18 in July, and their pupal weights fell from about 0·27 to 0·23 mg. over the same period, although at any given time pupal period was positively correlated with pupal weight. Female pupae were lighter than male pupae and had a shorter pupal period.

From March to July, a small but progressively increasing proportion of the pupae formed entered diapause; the proportion averaged less than four per cent. in June to July 1962–64. The pupal period ranged from 30 to 171 days, being less in later-formed pupae, so that a general emergence occurred in September–late October.
Some effects of resistance to organophosphorus insecticides in Myzus persicae (Sulz.) on the transmission of beet yellowing viruses
Authors: Russell G. E.
Published: July 2009

A population of Myzus persicae (Sulz.) that apparently showed resistance to organophosphorus insecticides was found on plants growing in glasshouses at the Plant Breeding Institute, Cambridge, in 1963. Experiments were conducted to compare the resistance to dimethoate and demeton-methyl of this population with that of another population, which had never been treated with insecticides. The resistant aphids were killed much more slowly than were susceptible aphids on plants sprayed with organophosphates, and they were able to transmit beet yellows virus (BYV) and beet mild yellowing virus (BMYV) to the treated plants. Under similar conditions, susceptible aphids were able to transmit BYV, a semi-persistent virus, but less efficiently than the resistant aphids, and were not able to transmit BMYV, a persistent virus, at all.

It is not known how common these organophosphorus-resistant populations of M. persicae are, at present, in the field in Britain. Under normal field conditions, control of such resistant aphids would be difficult, and virus yellows might, in consequence, become widespread even in crops that had been treated with organophosphorus chemicals.
Differences between six species of Cryptolestes (Coleoptera, Cucujidae) in susceptibility to methyl bromide vapour
Authors: Lefkovitch L. P.
Published: July 2009

Six species of Cryptolestes that occur in stored products (C. ferrugineus (Steph.), C. capensis (Waltl), G. pusillus (Schönh.), C. turcicus (Grouv.), C. pusilloides (Steel & Howe) and C. ugandae Steel & Howe) showed different susceptibilities to fumigation with methyl bromide at 30°C. and 80 per cent. relative humidity. The susceptibilities were partly correlated with morphological and bionomic differences between the species: C. ferrugineus was the least susceptible.
Ecological significance and practical implications of behaviour patterns determining the spatial structure of insect populations in stored grain
Authors: Surtees Gordon
Published: July 2009

The influence of population density, temperature, humidity and other environmental factors on the individual behaviour, aggregation in restricted parts of the habitat (accumulation) and spatial structure of the population (dispersion) of five species of beetles found in stored grain in Britain was the subject of laboratory studies by the author in 1959–65. In this paper, the results of these studies are drawn together, compared with field observations, and discussed in relation to behavioural mechanisms, ecology and control. The five species comprised Oryzaephilus surinamensis (L.), Tribolium castaneum (Hbst.).Cryptolestes ferrugineus (Steph.), Rhyzopertha dominica (F.) and Sitophilus granarius (L.). A basic plan of behaviour is considered to underlie the observed dispersion of these pests in grain, which may be summarised as follows: random movement of individuals causes disturbance within the population and leads to dispersal; accumulation occurs where individual movement is most restricted in response to environmental factors and where disturbance is consequently at a minimum.

The dispersion of O. surinamensis is almost entirely determined by kinesis mechanisms, and accumulation takes place in the warmest and dampest parts of a grain bulk. The dispersion of T. castaneum is determined to a lesser extent by kinesis mechanisms; accumulations take place in the drier parts of a bulk and at places where the temperature is about 25°C., but also in regions of damp grain if this is mouldy. The dispersion of C. jerrugineus is mainly determined by behaviour relating to the requirements of oviposition and feeding, which is superimposed on the basic plan. R. dominica accumulates in the driest parts of a grain bulk. The dispersion of S. granarius is largely determined by individual thigmotactic behaviour, so that accumulations are typically at the periphery of the grain bulk.

The ways in which a knowledge of the underlying causes of dispersion and accumulation aid in the detection and control of the pests and point to the optimum storage conditions are described.
Bionomics of Agrilus acutus (Thnb.) (Col., Buprestidae) on mesta (Hibiscus cannabinus) in India
Authors: Dutt Dilip Kumar
Published: July 2009

An account is given of the life-history of Agrilus acutus (Thnb.) (Buprestidae), a pest of ‘mesta’ (Hibiscus cannabinus) in india. The eggs are ovate and scale like, and are laid singly on the stem, usually near a leaf scar, and when kept at 31°C. and 73 per cent. relative humidity hatched on average in 12.4 days. The larva bores through the lower surface of the egg directly into the stem and feeds under the bark forming a sprial tunnel. A raised weal develops on the surface of the stem overlying the tunnel. Before each moult, the larva bores into the wood and makes a vertical chamber in which moulting occurs. There are normally three moults in the active feeding stages, but exceptionally four, and a prepupal moult. The rate of tunnelling is at first about 56 mm. per day and later eaches about 107 mm. The larval stage lests 26 days. The fully grown larva is 21 mm. long and bores into the wood to pupate, making a pupal chamber 11 mm. long into which it fits itself by adopting an asymmetrical U-shaped posture. After a prepupal stage of 2.5 days it pupates. The pupal period occupies about 11.7 days and a further seven days are spent by the adult in the pupal chamber. The adult female mates within a day of emergence from the stem. but does not oviposit until at least seven days have elapsed.
Acaricide trials against Rhipicephalus appendiculatus Neum., Amblyomma variegatum (F.) and Boophilus decoloratus (Koch) (Ixodidae) on cattle in Uganda
Authors: Matthysse John G. , Colbo Murray H. , Kamya E. P.
Published: July 2009

Field trials were conducted to compare toxicity and residual activity on cattle of 18 acaricides against Rhipicephalus appendiculatus Neum., Amblyomma variegatum (F.), and Boophilus decoloratus (Koch). Ticks were counted one, four and seven days after the cattle were sprayed. Each of the seven experiments involved three sprayings at seven- to eight-day intervals.

Toxaphene at 0.25 per cent., included as a standard, was relatively slow acting compared to organophosphorous and carbamate acaricides, but was equal to or better than most of the new acaricides in residual activity and over-all effectiveness. Carbaryl, Mopham and toxaphene were tested at the highest concertration, 0.5 per cent., and found to have the maximum over-all effectiveness, including maximum residual activity. Nevertheless, even these treatments did not protexct cattle against tick attachment and engorgement for as long as seven days.

All acaricides tested were very effective against B. decoloratus and A. variegatum, but none completely prevented attachment of R. appendiculatus foe as long as four days, even though all were very toxic to this tick. The smallest number (1.8 per beast) of R. appendiculatus attaching in four days occurred on the cattle sprayed with 0.5 per cent. carbaryl, but by seven days after spraying there were many ticks attached and some were already partially engorged. The inference is that none of the compounds tested gave promise of prevention of tick-borne disease transmission when used on a seven-day schedule. No inference is made concerning tick-borne disease control by reduction of tick numbers on the pasture land.

Mortality among ticks on the cattle one day after treatment was greatest for 0.1 per cent. coumaphos, 0.25 per cent. Prolate, 0.05 per cent. Bayer 9053, 0.2 per cent. Geigy GS 13006, 0.2 per cent. and 0.5 percent. carbaryl, 0.1 per cent dioxathion, 0.05 per cent. Bayer 9037, 0.1 per cent. prothidathion, 0.1 per cent. Dursban, 0.2 per cent. and 0.5 per cent. Mobam, 0.025 per cent. and 0.05 percent. chlorfenvinphos, 0.2 per cent. fenitrithion and 0.1 per cent. ethion. Mortalities of 83.1 per cent. to 88.5 per cent. were given by 0.05 per cent. diazinon, 0.1 per cent. bromophos-ethyl, 0.025 per cent. Dursban, and 0.5 per cent. toxaphene. Mortality below 74 per cent. was caused by 0.25 per cent. toxaphene, 0.2 per cent. bromocyelen, and 0.1 per cent. carbophenothion.
Distribution and trypanosome infection rates ofGlossina morsitans submorsitansNewst. along a trade cattle route in south-western Nigeria
Authors: Baldry D. A. T.
Published: July 2009

The distribution and trypanosome infection rates ofGlossina morsitans submorsitansNewst. were studied during the wet season of 1967 along 75 miles of the main trade cattle route which passes through the savannah country between Ilorin and Oyo in south-western Nigeria.

G.m. submorsitanswas found inhabiting open woodland, grassland, farmland and the environs of towns associated with the cattle route. In comparison with the types of habitat this species occupies in its zone of wide distribution in northern Nigeria, those habitats studied were considered atypical. It is suggested that the presence ofG.m. submorsitansin the area investigated had resulted from a southward population advance over the last 50 years and this hypothesis is discussed in relation to existing knowledge ofG.m. submorsitansadvances.

The trypanosome infection rates of 61.6 and 76.6 per cent, found in 364 examples ofG.m. submorsitansdissected are much higher than previously recorded for any of the subspecies ofG. morsitansWestw. A steady southward increase in the trypanosome infection rates ofG.m. submorsitanswas demonstrated for populations inhabiting 200 miles of cattle route. Trypanosome infections inG.m. submorsitansare attributed toTrypanosoma vivaxandT. congolense, and the absence ofbrucei-group infections is discussed in relation to the incidence ofT. bruceiinfections in trade cattle and limitations of the technique used for demonstrating infections in tsetse flies.

It is stressed that epizootiological aspects of the present findings cannot be clarified until reliable data on trypanosome infections of trade cattle in the area studied are available.
Pupal weight in relation to female age in Glossina austeni Newst
Authors: Jordan A. M. , Nash T. A. M. , Boyle J. A.
Published: July 2009

All of the pupae, totalling over 3,750, produced by 320 laboratory-bred females of Glossina austeni Newst. allowed to feed from rabbits’ ears, were weighed soon after deposition. Pupal weights were relatively low initially but increased during the first 30 days of the females’ productive life, were high during the next 100 days or so and thereafter declined to less than the initial level.
Apparatus for studying nocturnal patterns of oviposition and larval eclosion, and diel patterns of moth emergence
Authors: Baker C. R. B.
Published: July 2009

A photographic apparatus is described for obtaining a record of oviposition and larval eclosion at intervals through the night. By the use of electronic flash a negative silhouette image is produced and the method used does not appear to disturb the moths during oviposition. A second apparatus incorporating a moving pen is also described for studying and recording the times of emergence of moths from their pupae.
Assessment of the suitablity of Plagihammus spinipennis (Thoms.) (Col., Cerambycidae) as an agent for control of weeds of the genus Lantana (Verbenaceae). I. Life-history and capacity to damage L. camara in Hawaii
Authors: Harley K. L. S.
Published: July 2009

Plagiohammus spinipennis (Thorns.), a native of areas of Central and South America where rainfall exceeds 50 in. per annum, has been imported into Hawaii and Australia for the control of Lantana camara. The larvae girdle a stem of the host-plant and then tunnel extensively in the xylem tissues. In Hawaii multiple infestation of stems over 0-5 in. in thickness was found to be usual. Most attacks were within 25 in. of the ground and stems were killed or so severely weakened that they readily broke off, reducing tall plants to mutilated stumps eventually bearing small regrowth shoots. The life-cycle normally lasts one year.

An annual rainfall of at least 50 in. appears to be necessary for the development of large populations, and the amount that falls before and during the oviposition period influences larval survival. It is concluded that the insect should be very useful as a biological control agent for L. camara.
Indications concerning the flight activity of tsetse flies (Glossina morsitans Westw.) in the field
Authors: Bursell E. , Slack Ella
Published: July 2009

The content of proline, alanine and glutamate in the thorax of tsetse flies (Glossina morsitans Westw.) caught by two different sampling techniques is compared. Flies caught on a stationary bait animal have significantly less proline and significantly more alanine and glutamate than flies caught on a fly-round. The difference suggests that flies of the bait sample have been more active than flies of the fly-round sample during the period immediately preceding capture.
A method for the continuous rearing of the cabbage root flyErioischia brassicae(Bch.) and some observations on its biology
Authors: Finch S. , Coaker T. H.
Published: July 2009

A method for continuously rearing cabbage root fly,Erioischia brassicae(Bch.) is described.

Adult flies fed on sucrose, brewers’ yeast and yeast hydrolysate laid an average of 220 eggs per female when caged together in large numbers and 376 eggs per female when caged singly. Egg viability was 86 per cent. Egg hatch was severely reduced by relative humidities of less than 90 per cent, and the embryo became more susceptible to desiccation as it matured. The larvae were reared on swede, and maximum survival was obtained when the swedes were inoculated with an optimum number of eggs calculated from the ratio of 1 egg: 1.6 g. of swede. Different ratios were obtained from turnip and winter radish indicating that survival was probably related to the nutritional value of the rearing medium as well as to its availability. An average of 68 per cent, of the eggs placed on swede produced pupae that were equivalent in size to wild pupae. The fecundity of the flies was directly related to pupal weight and to the availability of protein in their diet. Adult longevity was reduced more by mutual disturbance than by any other factor.
Attraction ofAedes aegypti(L.): responses to human arms, carbon dioxide, and air currents in a new type of olfactometer
Authors: Mayer M. S. , James J. D.
Published: July 2009

A new type of olfactometer was designed to study the responses of mosquitos to various stimuli. Hosts could be displayed downwind as well as upwind from the mosquitos, and two hosts could be displayed simultaneously, one upwind from the other. Responses to radiations, if any, and to odours could be measured.

Mosquitos were not attracted downwind to an arm displayed within 61 cm., even when they were stimulated by CO2(under an incident illumination of about 10 foot-candles). About half the mosquitos showed a positive anemotactic response (i.e., they left the end downwind compartment in which they were released) in a current of room air, which undoubtedly contained human emanations. Only 15 per cent, responded to filtered air. Carbon dioxide caused no increase in response to filtered air but increased the number responding to room air (76 per cent, left the end down-wind compartment). Equal numbers of mosquitos responded to an arm displayed upwind in room air and in filtered air,i.e., about 83 per cent, left the end compartment. Carbon dioxide caused no increase in the number of mosquitos responding to an arm but increased the number responding to attenuated emanations from an arm. A repellent (deet) eliminated most of the response to an arm; the addition of carbon dioxide increased upwind flight to the treated arm, but many of the mosquitos flew past it. Carbon dioxide therefore appears to have a synergistic action with arm odours in the attraction of females ofAedes aegypti(L.). However, this conclusion does not exclude other behavioural effects of carbon dioxide demonstrated by other investigators.

Eesponses to arms in this new type of olfactometer were nearly identical to those obtained in another type previously used in a large-scale study. The testing confirmed earlier reports that mosquitos do not fly far in the same direction as wind-current and that host location was not possible through positive anemotaxis in the absence of light. Mosquitos were not attracted to a source of infra-red radiation.

The new direct method of comparing the attractiveness of different subjects demonstrated that mosquitos would leave the vicinity of one arm and migrate further upwind to another that was more attractive. Water and acetone rinses of human arms reduced attraction; acetone appeared to be a better solvent for the attractant substance than water.
A redescription of Culex vishnui Theo., with notes on C. pseudovishnui Colless and C. Tritaeniorhynchus Giles, from southern India
Authors: Reuben Rachel
Published: July 2009

The taxonomic status of the Culex vishnui group of species is discussed. Three species belonging to this group, C. vishnui Theo., C. pseudovishnui Colless and C. tritaeniorhynchus Giles, were recognised in the study area near Vellore, South India. All three species are described on the basis of adults and larvae, and keys for the identification of adults are provided.
Synoptic discussion of Lepidosaphes Shimer and its allies with a key to genera (Homoptera, Coccoidea, Diaspididae)
Authors: Williams D. J.
Published: July 2009

The author discusses the restriction of the genus Lepidosaphes to nine Holarctic species by Borchsenius and his assignment to other genera of most species previously placed in Lepidosaphes. These changes in generic assignment have affected the names of many species of economic importance. A key is presented to 13 genera allied to Lepidosaphes.
Comparative biology and ecology ofApanteles flavipes(Cam.) andA. sesamiaeCam. as parasites of graminaceous borers
Authors: Mohyuddin A. I.
Published: July 2009

A panteles flavipes(Cam.) andA. sesamiaeCam. are important parasites of graminaceous borers in the Oriental and Ethiopian Regions, respectively. Both have been utilised for biological control.A. sesamiaehas become the commonest parasite ofSesamia calamistisHmps. in Mauritius (Anon., 1954), whileA. flavipeshas become remarkably successful againstDiatraea saccharalis(F.) in Barbados (Simmonds, 1969a). In view of the interest engendered in these parasites, particularly the latter, by these successes, a general account is presented here of their biology, based on published data and on the author's observations at the East African Station (Kawanda, Uganda) of the Commonwealth Institute of Biological Control.
Laboratory studies on aggregation, size and fecundity in the black bean aphid, Aphis fabae Scop.
Authors: Dixon A. F. G. , Wratten S. D.
Published: July 2009

Adults of Aphis fabae Scop. can weigh from as little as 200 μg to as much as 1 800 μg (Way & Banks, 1967), a remarkable range in size for a single species. An extensive range in size also occurs among the adults in other species of aphid (Murdie, 1969a, b; Dixon, 1970). Small individuals result when aphids develop either under crowded conditions or on a mature host-plant; large aphids result when the nymphs are reared in isolation or on young or senescent host-plants (Way & Banks, 1967; Murdie, 1969a, b; Dixon, 1970). A small adult produces fewer nymphs and also smaller nymphs than average (Murdie, 1969b; Dixon, 1970). When aphids are overcrowded or feed on host-plants of poor quality, many aphids reach maturity that might otherwise fail to mature because of the ability of the species to produce viable adults of a great variety of size, including very small adults (Way & Banks, 1967).
The predatory and reproductive behaviour of Vestula lineaticeps (Sign.) (Hem., Reduviidae)
Authors: Parker A. H.
Published: July 2009

Observations on the sexual behaviour, oviposition and responses to insect prey of the predatory Reduviid Vestula lineaticeps (Sign.) were made in the laboratory. Experiments with cardboard models indicated the importance of moving visual stimuli in eliciting predatory responses, but provided no evidence that olfactory stimuli play any such role. The responses of adult females towards other adults were apparently purely predatory. Males did not visibly discriminate between living females and other specimens (dead females, living or dead males) until they had seized them, when they displayed sexual responses with the living females and usually purely predatory behaviour with the remainder.
Parous rates in some Amazonian mosquitoes collected by three different methods
Authors: Davies John B. , Corbet Philip S. , Gillies M. T. , McCrae A. W. R.
Published: July 2009

A total of 4418 mosquitoes caught by three collection methods at two levels in the forest near Belém, Brazil, were dissected to determine the proportion of parous individuals. About two-thirds of the mosquitoes belonged to Culex (Melanoconion) portesi Senevet & Abonnenc and C. (M.) taeniopus D. & K. The dissection technique entailed dissecting out the ovaries for examination of the tracheoles, whilst preserving the rest of the mosquito for later processing for virus recovery. Analysis of the results showed that, although significant differences were found in the parous rates from samples caught off human bait, and from mouse-baited Trinidad no. 17 and blower traps, these differences were unlikely to be of practical value when compared to differences in catching ability and ease of operation of the methods. In all, 2771 mosquitoes were classed as parous, and these when inoculated into baby mice in 142 pools yielded 14 isolations. It was concluded that the technique used did not reduce the likelihood of isolating viruses from the dissected mosquitoes.
Some species of Atherigona Rondani (Diptera, Muscidae) from northern Nigeria, with special reference to those injurious to cereal crops
Authors: Deeming J. C.
Published: July 2009

During investigations into shoot-fly damage to guinea corn (Sorghum bicolor), millet (Pennisetum typhoides) and maize (Zea mays) in rain-grown plots at Samaru during 1966, it became obvious that attack was not attributable to a single species (Atherigona varia var. soccata Rondani (=A. indica infuscata van Emden)), as was previously believed. This species is undoubtedly the principal pest of guinea corn seedlings and young plants in northern Nigeria (Map 1), but there are also many other species involved. During the following four years field trials were undertaken to establish the relative importance of the species within the area and to learn something of their biology.
The behaviour of the adult ofAphodius tasmaniaeHope (Col., Scarabaeidae) in South Australia.
Authors: Maelzer D. A.
Published: July 2009

In the lower South-East of South Australia, adults of Aphodius tasmaniae Hope, which is an economic pest of improved pastures, emerge from the soil 2–3 days after rain has fallen in summer. The females may lay two batches of eggs. The first batch (about 35 eggs) is developed at the expense of the fat-body and is laid 3–6 days after emergence; a second batch (about 20 eggs) can be developed and laid after the female has fed on dung.

The beetles are crepuscular and fly after sunset if the weather is suitable for flight. The first batch of eggs may or may not be laid before flight, depending on the weather. Until the fat-body is largely depleted, beetles fly with the wind and are attracted to lights, but after that stage has been reached they fly upwind to dung and are not attracted to lights. After feeding on dung for a few days the females become gravid again, and apparently change their responses to light and wind once more. The distribution of larvae in the field suggested that adults aggregated and laid eggs in specific places. The factors which promote aggregations of adults were therefore studied.

The survival-rate of the females and the number of eggs they laid in two soils, a sand and a clay loam, were related to the ‘available water’ in soil as measured by the pF scale. Females survived in largest numbers and laid most eggs in the range of pF 2·8–3·2 in both soils. Similarly, when given a choice of a number of water contents in soil, beetles aggregated in largest numbers within the range 2·8–3·2 in one soil and pF 2·8–3·5 in another. In the latter soil, however, the pF values that were tested were more widely spaced, and it is suggested that the combined data are only intelligible if there was an optimum range of pF within the vicinity of 2·8–3·2 in both soils. These and other experiments indicated that moisture in soil was the major factor capable of' promoting aggregations of adults.

When water was not limiting, aggregations of beetles occurred on loose as opposed to compact surfaces. However, ‘shelter’ (dry grass stems broken off the parent plant, dung, etc.) was capable of promoting aggregations even if the soil underneath ordinarily inhibited burrowing. Aggregations of beetles also occurred on surfaces into which other beetles had previously burrowed; this was probably due not to any attraction of beetles to other beetles, but to loosening of the surface soil by the original beetles, which permitted later arrivals to burrow rapidly.

It is probable that the patchy distribution of larvae in the field is due to the aggregation of the adults in the field mainly in relation to moisture in soil, type of surface and shelter. It is also suggested that aggregations of larvae that occur around conspicuous objects, such as trees, result from beetles colliding with these objects by chance when they are flying after dark, dropping to the ground and burrowing into the soil to lay eggs there.
Observations on emergence and life-span of wheat bulb fly, Leptohylemyia coarctata (Fall.), under field-cage conditions.
Authors: Dobson Ronald M. , Morris Marjory G.
Published: July 2009

Emergence and life-span of wheat bulb fly, Leptohylemyia coarctata (Fall.), have been studied by the use of a field-cage-marking technique. Emergence was investigated by observing the numbers of flies emerging daily from an area of infested wheat enclosed by a cage of fine mosquito-netting, and life-span by making a daily census of marked and individually recognisable flies which had been liberated in the cage. Flies were handled only when being marked and in the later part of the work all observations were made without touching either them or the wheat.

Flies were chilled to render them comatose for marking and under certain circumstances this and the marking was-harmful. Attempts were made to reduce these harmful effects.

Emergence dates varied from year to year depending on the temperatures of spring and early summer, and there were also considerable differences between the emergence dates of populations of adjacent fields in the same year. Consistently, males appeared before females.

The ratio of the number of flies seen to the number known to be alive on each day varied according to weather, flies being more difficult to find on windy days than on calm ones and on bright days than on dull ones.

The observed life-spans of both sexes varied greatly, up to a maximum of 75 days for females and 55 days for males. An exact statement of mean life-span was not possible because there was a tendency for flies emerging later in the season to be less long-lived than those emerging earlier. Most flies of both sexes lived for over 30 days.

The observed life-spans fall short of the true life-spans by amounts that depend on the proportions of living flies seen each day. Two methods are shown by which the mean unrecorded life-span can be calculated.
Descriptions, and notes on the biology, of four new species of Adelgidae from West Pakistan
Authors: Yaseen Maajid , Ghani M. A.
Published: July 2009

The bionomics and ecology of two Adelgids, Adelges knucheli (Schneider-Orelli & Schneider) and A. joshii (Schneider-Orelli & Schneider), first recorded from West Pakistan by Yaseen & Ghani (1966), have been studied by Ghani & Rao (1966). During surveys for the natural enemies of Adelgids in West Pakistan forests, another Adelges sp. on fir and three Pineus spp. on pines were found. They differed from described species in shape, size and arrangement of the wax pores on the sclerotised plates of the head and thorax, characters considered by Underwood (1963) the best for identifying apterous Adelgid adults. They are here described as new, and notes are given on their biologies seen in marked colonies under field conditions. All four species are monomorphic and anholocyclic.
Factors affecting the status of a virus as a control agent for the potato moth (Phthorimaea operculella (Zell.) (Lep., Gelechiidae)
Authors: Reed E. M.
Published: July 2009

This paper describes some characteristics of a granulosis virus specific to the larvae of potato moth (Phthorimaea operculella (Zell.)). Host eggs are laid on the soil or on the potato plant; the newly hatched larvae bore into the leaves, generally through the underside, and then develop in feeding tunnels. Mines occur more frequently on the lower leaves, and on the outermost and larger leaflets. The adults are dispersed by wind. Exposure of larvae to externally borne virus deposits is very brief, but sprays of the virus usually produce high rates of infection even when applied only to the upper surfaces of the leaves. It was established that virus particles can enter treated leaves through the stomata. Infected larvae die in two to three weeks, but an overdose causes death by toxicosis within 48 h. In two small-scale field trials the disease spread to control plots preventing comparison of damage to tubers of treated and untreated plants. In each trial, the sprays started an epizootic which affected almost all larvae on the treated plants. With high host populations and many volunteer plants, the epizootic spread at least 1 000 yd in five years. Under good commercial conditions with low host populations, wind and birds were the chief means of virus spread. The distribution and retention of virus particles on the plant were affected by wetting agents and virus concentration.
Trials of residual sprays of Mobam and carbaryl against mosquitoes in verandah-trap huts at Taveta, Kenya
Authors: Hudson J. E.
Published: July 2009

Two carbamate insecticides, Mobam (4-benzothienyl methylcarbamate) and carbaryl, were tested at dosages of 2 g/m2 active ingredient in grass-roofed verandah-trap huts at Taveta, Kenya, in 1967 and 1968, respectively. In Mobamtreated huts, overall mortalities were over 70% for 20 weeks in Anopheles gambiae Giles and A. funestus Giles, and for 12 weeks in Culex pipiens fatigans Wied. In the carboryl-treated huts overall mortalities were over 70% for 12 weeks in A. funestus, but in A. gambiae and C.p. fatigans never exceeded 64% and 33%, respectively. Neither compound had a deterrent effect on A. gambiae, which entered the treated huts in more than the expected numbers. Mobam did not appear to be repellent; and carbaryl was only slightly so. Egress of blood-fed A. gambiae increased after treatment but most of the mosquitoes died after reaching the verandah traps. There were slightly more unfed A. gambiae in the treated huts than in the control hut but there were never more than 35% unfed.
On the biology of the adult of the almond wasp,Eurytoma amygdaliEnd. (Hym., Eurytomidae), in Israel
Authors: Plaut H. N.
Published: July 2009

Field and laboratory observations on the adults ofEurytoma amygdaliEnd. at Newe Ya'ar, Israel, were made as a basis for improving control measures against this pest of almond fruits. After hatching from the pupa, the adults took 3–9 days to bore through the pericarp. Emergence usually began in March, but was delayed by cold weather in February and March. Males emerged earlier than females, and oviposition began the first or second day after emergence. Drilling and deposition of the egg into the nucellar tissue of the young fruits took 9–34 min, up to five eggs per fruit being laid under natural conditions. As oviposition sites, larger fruits were preferred to small, and uninfested fruits to infested. At 23 °C indoors fecundity and life span were 128·9 and 7–18 days, respectively, but outdoors under unsettled weather conditions were 23·0 and 4–25 days, respectively. When fed on honey dew or water instead of 10% honey, fewer eggs were laid. The lack of an oviposition site reduced the life span of the female.
Techniques for pheromone bioassay studies of ants
Authors: Robertson Phyllis L. , Orton C. J.
Published: July 2009

Techniques and apparatus developed for pheromone bioassay studies of ants are described. They include a ventilated cage, with a blacked-out nest area and a two-compartment arena, in which colonies are maintained in the laboratory, and in which group experiments are carried out; a prey treatment apparatus, in which a stinging ant is clamped at the junction of head and thorax, with its body supported on a length of black nylon tubing which is used as artificial prey after it has been stung for a specified period; an applicator for introducing into the cage artificial prey which have been treated with ant secretions, either by the latter method, or by the direct application of dissected gland material; and a closed-system, pheromone-testing apparatus, in which an ant is held in a perspex observation chamber with controlled lighting, supplied with air at constant temperature, relative humidity and flow rate, and treated with gland odours introduced into the conditioned air.
Effects of synthetic juvenile hormone and a juvenile hormone analogue, methyl farnesoate dihydrochloride, on pupal development of the yellow mealworm Tenebrio molitor L.
Authors: Critchley B. R. , Campion D. G.
Published: July 2009

The result of treating Tenebrio molitor L. pupae with synthetic juvenile hormone (JH) or a juvenile hormone analogue, methyl farnesoate dihydrochloride (DMF), is to arrest pupal development, producing pupal/adult intermediates. Both substances induced approximately 50% pupal/adult intermediates at a topically applied dose of 1 μg. The activity was greatly affected by the age of the pupa at the time of treatment, one- and two-day-old pupae being the most sensitive. Applied to four-day-old and older pupae complete metamorphosis to the adult was possible at a dose of 8 μg of synthetic JH and up to 200 μg for DMF. Doses above these levels merely increased toxicity without juvenilising activity.
Artificial Refuges for tsetse flies (Glossina spp.)
Authors: Vale G. A.
Published: July 2009

In Rhodesia from 1966 to 1970 Glossina morsitans Westw. and G. pallidipesAust. in natural and artificial refuges were studied by in situ counts or captured by a hand-net, mechanical, electric or sticky trapping, or a curtain drawn across the entrance. A modification of mechanical trapping permitted investigation of the pattern in whichtsetse vacated a refuge. Coolness and shade were features of effective refuges. Large numbers of tsetse utilised refuges only during the hot dry months of September, October and November. Entries occurred when temperatures reached 32°C in the morning and continued until mid-afternoon; exits occurred mainly in the evening. G. morsitansentering at 12.00–14.00 h were relatively abundant in fat; G. pallidipes entering at 12.00–16.00 h were relatively abundant in residual blood-meal. Greatest numbers of tsetse occupied refuges in naturally shaded situations such as riverine fringes. Few of the many tsetse marked in refuges and releasedwere found again at the refuge of marking. Artificial refuges were not used extensively for larval deposition. Comparisons between the catches from refuges, oxen, Morris traps and a fly round illustrate the problem of obtaining representative samples of tsetse populations. The application of insecticides to natural refuges is a policy of merit.
A Ponerine ant (Hym., Formicidae) associated with Homoptera on cocoa in Ghana
Authors: Evans H. C. , Leston Dennis
Published: July 2009

The Ponerine ant Odontomachus haematodus (L.) tendsthe aphid Toxoptera aurantii (Boy.) and a StictococcidStictococcus sjostedti Ckll. on cocoa in Ghana but predates the mealybug Planococcoides njalensis (Laing). Tents are built over the first two, largely of soil particles. Honeydew is collected in the mandibles and carried to the nest or may be accumulated and eventually drunk. Some of the soil used in the tents is infected by blackpod sporangia. Tending homopters is restricted to the immediate vicinity of the nest. The mutualism practised has evolved independently of its occurrence in higher ants.
A new Agromyzid (Diptera) from Pakistan feeding as a stem-borer in Convolvulus arvensis
Authors: Spencer Kenneth A.
Published: July 2009

Melanagromyza convolvuli from the stems of Convolvulus arvensis in West Pakistan is described as new.
A new species of Dysmicoccus Ferris (Pseudococcidae, Homoptera) on banana.
Authors: Williams D. J.
Published: July 2009

The following species taken in London on imported bananas has been submitted recently for identification and has proved to be a new species of Dysmicoccus Ferris.

On checking some unidentified material in the British Museum (Natural History), the same species has come to light on imported bananas collected in London earlier. As some of these were labelled “from Canary bananas”, a check was made of all the material in the British Museum (N. H.) of mealybugs from the Canary Islands and it is evident that the species is widespread there but has been misidentified as Pseudococcus comstocki (Kuw.). Furthermore, it has been misidentified as this species on other occasions on imported bananas in England and Egypt and although some of the preparations concerned are labelled as from Canary bananas, it is not possible to determine whether all have come from this source.
The effect of a residual house-spraying campaign in East Africa on species balance in the Anopheles funestus group. The replacement of A. funestus Giles by A. rivulorum Leeson.
Authors: Gillies M. T. , Smith A.
Published: July 2009

In the course of an experiment in malaria control in an inland region of Kenya and Tanganyika, by the use of house spraying with dieldrin, routine catches were maintained of mosquitos resting in artificial outdoor shelters. During the 18 months of the pre-spraying period, catches in the South Pare district of Tanganyika mainly consisted of the principal vectors, Anopheles gambiae Giles and A. funestus Giles, together with small numbers of A. rivulorum Leeson.

During the three years following the spraying, A. funestus disappeared almost completely from the catches, while A. rivulorum showed an increase of about seven times above its former level.
The eradication of Glossina morsitans submorsitans Newst. and Glossina tachinoides Westw. in part of a river flood plain in Northern Nigeria by chemical means. Part III.
Authors: Davies H. , Blasdale P.
Published: July 2009

An account is given of work carried out during the third year to eradicate Glossina morsitans submorsitans Newst. and G. tachinoides Westw. from an elongated fly-belt situated in the Sudan savannah vegetational zone of Northern Nigeria, which is an important cattle-raising area.

The total area of the fly-belt, which is isolated as far as G. morsitans is concerned, measures about 120 miles in length and extends, in places, up to almost 10 miles in width. The country involved forms the flood plains and adjacent uplands of the Komadugu Gana river.

Sixty-nine sq. miles were sprayed with DDT during the 1957–58 dry season(between end of January and end of April 1958), and 18 months after completion of work no tsetse has been found in the treated area. These 69 sq. miles formed the dry-season habitat of the fly on this section of the river, and the cost of insecticide and labour involved amounted to approximately £86 per sq. mile. As the zone infested in the wet season greatly exceeded this dry-season concentration area, reclamation costs per sq. mile, when applied to the amount of grazing land made safe for cattle, amounted to much less than the figure quoted.

Successful continuation of this project is ascribed to three salient features of the technique employed: —

(a) A single application only, of a 3·75 per cent, aqueous suspension of DDT from a wettable powder, is sufficient for complete eradication.

(b) A high degree of discriminative or selective spraying is possible: for the elimination of G. morsitans, spraying can be mostly confined to larger tree trunks, in shade, up to a hei ght of about 5 ft.

(c) Artificial or natural barriers to isolate each season's work, and so prevent re-invasion, are not necessary where the fly-belt is of a comparatively narrow and elongated nature. Spraying the re-infested area during the following season is more economical.
The natural enemies of the lettuce root aphid, Pemphigus bursarius (L.).
Authors: Dunn J. A.
Published: July 2009

Because the lettuce root aphid, Pemphigus bursarius (L.), is gall-inhabiting on poplar in spring and lives underground on lettuce during summer, its naturalenemy complex differs from that associated with foliage-feeding aphids. It suffers little from parasites and only fundatrices have been found attacked. The only species reared from parasitised individuals was the Pteromalid, Pachyneuron sp., which is assumed to be hyperparasitic. When the galls open at migration time, Syrphid larvae and Anthocorids can enter and attack the contents. Anthocoris nemorum (L.) and A. nemoralis (F.) are the main predators at this stage. Before they begin feeding, they kill all the aphids within a gall extremely quickly and efficiently. It is suggested that the aphids may be killed by a secretion from the stink glands of the Anthocorids working as a fumigant within the confines of the gall. Several Staphylinids and Carabids are frequently associated with subterranean colonies of P. bursarius and are almost certainly predators. The larvae of the Chloropids, Thaumatomyia glabra (Mg.) and T. notata (Mg.), are common predators of P. bursarius in the soil. The sexuparae, both before they leave the lettuce plants and on their arrival on poplar, are attacked by three species of Coccinellid.
The white coffee borer, Anthores leuconotus Pasc., and its control.
Authors: Tapley R. G.
Published: July 2009

Anthores leuconotus Pasc., indigenous in East, South-East, South and South-West Africa, is an important ring-barking and wood-boring pest of the main stem and root of arabica coffee. The duration of the life-cycle ranges from 12 to 25 months, with most individuals requiring 16–20 months. Thus beetles developed from eggs laid during the long rains (April–June) of one year will mostly emerge during the short rains (Nov.–Jan.) of the following year, with some appearing during the rains preceding and others during the ensuing rains.

If the mean life-cycle is taken to be 18 months, the approximate duration of each stage is as follows:— eggs require 21–23 days for eclosion; larvae in the
first five instars ring-bark the tree for 4 months, and those in the final two instars bore into the wood for 12 months; the pupal period lasts about 4½ weeks, and the beetle remains in the tree for a further two weeks before emerging.