bluuebunny/crossref_metadata_2025 huggingface dataset:
Observations on the Life-history of the Red Locust, Nomadacris septemfasciata (Serv.) in the solitary Phase
Authors: Burnett G. F.
Published: July 2009

The populations of Nomadacris septemfasciata described in this paper were all of solitaria or neai-solitaria phase.

Sexual maturation as measured by the developing ovaries took place rapidly though irregularly through the population. Its onset coincided with an increase in the daily number of hours of relative humidity at or above 75 per cent., and abundance of green food; Copulation, which started after the first wide-spread rain, took place before the ovaries of many females were completely mature.

Caged locusts gave a mean fecundity of 183 eggs contained in 2·4 pods which is probably a minimum figure. Pods were laid at intervals of about two weeks and each was laid before the next batch had visibly developed.

The period spent in the egg was at least 39 days, at most 46 days and probably 42 days. Adults appeared 67 days after the first hatchings. Both these periods are greater than those recorded in phase transiens or gregaria.

Solitaria locusts were found to pass through seven instead of six nymphal instars as do gregaria. This difference seemed to be constant. The extra instar was probably interpolated between the second and third of gregaria but was not an exact duplicate of any other instar.

The number of vertical dark eye-stripes is a convenient and fairly constant indicator of the instar. The number of antennal segments in the later instars and in the adult, and also the number of adult eye-stripes, is greater in the solitaria phase.

Amongst the hoppers three main types of coloration were encountered and are briefly described but they could not be closely related to phase. The amount of dark pigment present in late stage nymphs was reflected in the young adult, the appearance of which is described in some detail. Subsequent changes during the dry season are briefly noted, in particular the pink of the hind wing, which becomes faintly visible within a month of the last moult.

The changes in pigmentation which take place during sexual maturation are described in detail. In addition to pronounced darkening of the tegmina which completely changes the appearance of the solitaria locust, certain bright pigments are laid down which are later obscured by a general blackening. It is unsafe to classify Nomadacris septemfasciata as to phase on colour alone unless the date of capture and its relation to the breeding season in the locality is taken into consideration. Solitaria do not normally develop the general reddening of the body which is shown by migrating swarms, even when these are only transiens in phase.
DDT-resistance in Plutella maculipennis (Curt.) (Lep.) in Java
Authors: Ankersmit G. W.
Published: July 2009

The diamond-back moth, Plutella maculipennis, and Crocidolomia binotalis are the main pests of cabbage in Indonesia. Until 1951, good control was obtained with DDT sprays and dusts, but in that year growers near Lembang (Bandung) obtained poor results with DDT against P. maculipennis as compared with previous years. Investigations were started in Lembang, and also in Patjet (on Mt. Gedeh) where no difficulties had arisen. In laboratory experiments, a marked difference in susceptibility to DDT between a Lembang and a Patjet strain of P. maculipennis was demonstrated.

In field tests near Patjet with DDT, BHC and toxaphene, DDT gave satisfactory control and was better than the other two. At Lembang, however, where these three materials were again tested, but with derris and pyrethrum also, toxaphene was the most effective, followed by derris and BHC, while DDT, and also pyrethrum, gave almost no control.

For the time being, toxaphene and derris are recommended, the former during the growing season and the latter subsequently, but it is feared that resistance to toxaphene will develop. It may become necessary to resort to cultural and biological measures.
On the Evening Biting Activity of three neotropical Anopheles in Trinidad, British West Indies
Authors: Senior White R. A.
Published: July 2009

Lumsden's “standard sunset” period observations have been repeated with the three commonest species of Anopheles occurring in Trinidad. The method was modified to yield data on the ovarian and fertilisation states of these three species over a period of ten months which included the dates of the latest and earliest sunset at 10°N.

A. aquasalis comprised nearly 95 per cent. of a total catch of 8,592 specimens. Just over 18 per cent. of those that attacked were newly emerged, and no more than half of these were fertilised. Relict eggs, denoting a second or later gonotrophic cycle, were found in February, June and July. The 40 minutes from sunset + 20 minutes yielded nearly 80 per cent. of the total of the first two hours of activity, this period comprising nearly half the estimated total night's attack. From one hour after sunset the proportion of newly emerged specimens that attack is well below the mean. The second hour after sunset therefore provided the greatest infection risk when age, not numbers attacking, is considered.
On a new Species of Saissetia (Hem.: Coccoidea) from Zanzibar
Authors: Williams D. J.
Published: July 2009

The following Coccid was first recorded as a probable new species of Saissetia by Dr. W. J. Hall in Nutman and Sheffield (1949, p. 437), who suggested that it might be regarded as a possible vector, should a virus be the cause of Suddendeath disease of cloves. Although further research has shown that this disease is not caused by a virus, the species is of particular interest in its relationship with ants and this has been the subject of a special study by M. J. Way (in press).
Aircraft Applications of Insecticides in East Africa. II.—An experimental Attempt to Produce a Fly-free Corridor through a Belt of Tsetse-infested Woodland
Authors: Hocking K. S. , Parr H. C. M. , Yeo D. , Robins P. A.
Published: July 2009

An experimental attempt was made to produce a fly-free corridor through a belt of savannah woodland containing the tsetse flyG. swynnertoni.

An area two miles wide and four miles long was treated with a coarse spray of a 4·6 per cent, w/v solution of DDT in Shell Diesoline. The dosage per application was 0·5 gallons per acre, and seven applications were made, at intervals of approximately two weeks, so that the treatment covered two pupal periods.

The fly density had fallen to a very low level by the end of the experiment, and the area remained virtually free from flies for the subsequent two months. An examination of the data suggests, however, that the fly population was maintained largely by immigrant flies, and was certainly subject to wide variations, and it seems certain that the effect of the applications would have been considerably less upon a stable, self-supporting population.

The drop spectrum of the ground deposit had a mass median diameter of 0·35 mm., and the recovery of insecticide in the area was approximately 60 per cent. Leeward and under sides of obstacles did not receive a dose although in some cases dosages were obtained on apparently leeward sides, probably because of local reversals of wind direction.
The responses of Prostephanus truncatus (Coleoptera: Bostrichidae) and Sitophilus zeamais (Coleoptera: Curculionidae) to pheromone and synthetic maize volatiles as lures in crevice or flight traps
Authors: Hodges R.J. , Hall D.R. , Mbugua J.N. , Likhayo P.W.
Published: July 2009

Flight traps and crevice traps for catching Prostephanus truncatus (Horn) and Sitophilus zeamais Motschulsky were studied in Kenya. The traps were baited with pheromones of these beetles, with or without synthetic maize volatiles. In the case of P. truncatus, which has a two component pheromone consisting of Trunc-call 1 (T1) and Trunc-call 2 (T2), the components were tested singly or in a 1:1 combination. The addition of synthetic maize volatiles to pheromone traps did not result in an increase in trap catch of either S. zeamais or P. truncatus. The pheromone of S. zeamais was an effective lure in both crevice and flight traps but the actual numbers captured were low. Captures with traps baited for P. truncatus were much greater. The response of P. truncatus to the two components of its pheromone was affected by the type of trap used. Crevice traps baited with either component alone caught fewer beetles than those baited with a mixture. In contrast, flight traps baited with T2 or the mixture were equally effective while traps with only T1 caught significantly fewer than either of these. These observations clarified apparent discrepancies between earlier studies in Tanzania and Mexico and are used to derive an hypothesis about the roles of T1 and T2; T2 appears to be a long-range attractant and T1 important for modifying the response to T2 to facilitate close-range orientation. Adult P. truncatus arriving at the traps were sexed, and in both flight and crevice traps the majority of captures were females even though in the experimental maize cribs the beetles were present in a roughly equal sex ratio. The role of the pheromone is discussed in the light of this observation.
Weather associated with autumn and winter migrations of rice pests and other insects in south-eastern and eastern Asia
Authors: Rutter J.F. , Mills A.P. , Rosenberg L.J.
Published: July 2009

Trajectory analysis was used to determine the direction and extent of windborne migrations of insects trapped in autumn and winter in south-east and east Asia for 12 years between 1968 and 1987. Nearly 2600 trajectories were drawn upwind at 10 m and 1.5 km from 15 catching sites and within the time (⋜60 h), wind speed (⋝5 km h-1) and temperature (⋝10°C) thresholds used, only 5% of the trajectories failed to locate a possible source and over 90% were completed in 40 h or less. The delphacids Nilaparvata lugens Stål and Sogatella furcifera (Horváth) dominated the trap catches (96%) with Cicadellidae (2.3%) and Diptera (0.5%) as the next most numerous. Very few Lepidoptera were reported (<0.3%). Nearly 80% of the trajectories were constructed in the prevailing Winter Monsoon and Trade winds, resulting in a southward displacement of insects towards putative overwintering areas as reported in previous studies. Tropical cyclones in autumn, produced trajectories which differed in both direction and extent from those in the prevailing winds, supporting the suggestion that the contraction of the distribution areas of rice pests at this time of year is the product of a series of movements in different directions. The results suggest that migrations continue throughout the year in the tropics and sub-tropics and indicate that this may be one way the capacity for long distance migration is maintained in some rice pest populations.
Control of summer and winter diapause in Pidorus euchromioides (Lepidoptera: Zygaenidae) on Chinese sweetleaf Symplocos chinensis
Authors: Fangsen Xue , Kallenborn H. G.
Published: July 2009

Pidorus euchromioides Walker has two separate diapauses during its life cycle, a winter diapause as a fourth larval instar and a summer diapause as a prepupa in a cocoon. Winter diapause was induced by short photoperiods. The critical day length of 13 h 20 min to 13 h 40 min at 23.3°C under insectary conditions was very similar to the critical day length (13 h 32 min) observed in the field. Sensitivity to day length was restricted to the first 9 days, corresponding to the first and second instars. The duration of larval diapause was not only strongly correlated with the inducing photoperiod, but also dependent on the number of short days experienced during the larval growth period. The shortest diapause occurred at the critical day length, or when the larvae were exposed for 6 days (a critical number of short days) to a photoperiod of LD 12 h:12 h. The summer diapause appeared to be primarily determined by a genetic factor and only occurred in part of the overwintering generation and the first generation. The two different diapause mechanisms play important roles. Winter diapause ensures that P. euchromioides synchronizes its development and activity with the phenology of specific host plants, and summer diapause provides the species with a high degree of adaptation to an unpredictable environment.
The karyotype of Bemisia tabaci (Hemiptera: Aleyrodidae)
Authors: Blackman R. L , Cahill M
Published: July 2009

Whiteflies of the Bemisia tabaci (Gennadius) group are a major and increasing problem for agriculture throughout the world. In particular, the appearance and rapid spread of a highly virulent new form (silver-leaf whitefly, or B-biotype; Brown et ah, 1995), and recognition that the problem involves a complex of sibling species, host races and/or biotypes has stimulated intensive multidisciplinary research on this insect in recent years (Gerling & Mayer, 1996).
Life-history parameters of different biotypes ofBemisia tabaci(Hemiptera: Aleyrodidae) in relation to temperature and host plant: a selective review
Authors: Drost Y.C. , van Lenteren J.C. , van Roermund H.J.W.
Published: July 2009

Life-history parameters of different biotypes of the whiteflyBemisia tabaci(Gennadius) species complex were reviewed. This included the B-biotype ofB. tabaci, identified asB. argentifolii(Bellows & Perring). Comparisons were made among different biotypes on cotton, among host plants for biotype B and among the whitefly speciesB. tabaciandTrialeurodes vaporariorum(Westwood), the greenhouse whitefly. The biotype identification of different populations ofB. tabaciwas summarized in a table. Biotypes discussed were A, B, Indian and biotypes of the Old World group. Temperature dependent relationships were estimated for egg development rate, development rate from egg to adult, immature mortality, adult longevity, sex-ratio, pre-oviposition period and fecundity. The fitted curves will be used as input for a simulation model of the population dynamics ofB. tabaciin a greenhouse when parasitoids are released. The model makes it possible to evaluate the integrated effect of different life-history parameters and behavioural parameters of parasitoids on whitefly population levels in a greenhouse.
The influence of the juvenile hormone analogue (S)-hydroprene onAprostocetus hagenowii(Hymenoptera: Eulophidae), an oothecal parasitoid of the oriental cockroachBlatta orientalis(Dictyoptera: Blattidae)
Authors: Bell H.A. , Marris G.C. , Edwards J.P.
Published: July 2009

The synthetic juvenile hormone analogue (S)-hydroprene can control populations of the oriental cockroachBlatta orientalisLinnaeus. Eradication ofB. orientalisinfestations, however, can take in excess of two years. In an attempt to reduce the time (S)-hydroprene takes to eliminate a population of oriental cockroaches, we explored the possibility of using the oothecal endoparasitoidAprostocetus hagenowiiRatzeburg in combination with (S)-hydroprene. For such a strategy to be successful, it is important that the parasitoid remains substantially unaffected by (S)-hydroprene. WhenA. hagenowiiwas exposed toB. orientalisoothecae in the presence of (S)-hydroprene, female parasitoids showed no reduction in their capacity to attack hosts and their fecundity was not compromised. (S)-hydroprene, at dose rates of 18 mg/m2and 100 mg/m2, induced deformity in approximately 12% and 33% respectively of parasitoids that emerged. No reduction in reproductive viability was seen in morphologically normal F1parasitoids. Deformed F1parasitoids, exposed to the higher (S)-hydroprene dose, showed a 71% reduction in the number of oothecae attacked and a 50% reduction in the number of offspring produced. These results indicate thatA. hagenowiicould be used in combination with (S)-hydroprene in an integrated pest management programme againstB. orientalis.
Cytogenetic analysis of a new subcomplex of Simulium exiguum (Diptera: Simuliidae) in amazonian Ecuador
Authors: Charalambous M. , Arzube M. , Lowell S.
Published: July 2009

Two new cytotypes of the onchocerciasis vector blackfly Simulium exiguum Roubaud are described from amazonian Ecuador. As transmission of the disease does not occur in the region, the two cytotypes are not currently vectors, The Napo form (N = 113) differs cytologically from the chromosomal standard of the species, the Cayapa form, through possession of the fixed paracentric inversions IL-E and IIIL-L; the Huatarac form (N = 22) differs by the fixed inversions IL-L and IIIL-D + L. Both forms form a subcomplex, termed the ‘amazonian’ subcomplex, through sharing the fixed inversion IIIL-L. They also share a number of polymorphic inversions, but neither form possesses sex-linked inversions. The fixed and sex-linked inversions of the previously described Aguarico form were found to be polymorphic and autosomal in the Napo and Huatarac forms, suggesting a close genetic relationship among these forms. The Napo form is distributed throughout the Napo river system (except in the Rio Huatarac) and found in the Rio Aguarico, whereas the Huatarac form is unique to the Rio Huatarac. As their distributions in this study were allopatric, the species status of the two cytotypes could not be tested. The Aguarico form was not found in the Rio Aguarico, nor in any of the other rivers sampled. Whether the Napo form has replaced the Aguarico form in the Rio Aguarico, or whether its absence is due to seasonal variation requires further investigation.
Does a repellent effect contribute to reduced levels of insect activity in dung from cattle treated with ivermectin?
Authors: Floate K.D.
Published: July 2009

A two-year pitfall trapping study was performed to test the preference of coprophilous beetles (Hydrophilidae, Scarabaeidae, Staphylinidae) for dung from untreated cattle versus dung from cattle treated topically one or four weeks previously with a recommended dose of ivermectin in a pour-on formulation. In 1994, significantly more Aphodius fimetarius (Linnaeus) and A. distinctus (O.F. Müller) at each of two sites were collected with dung from treated cattle. No differences were detected for other taxa. In 1995, significantly fewer individuals of ten taxa, including A. fimetarius and A. distinctus, were collected with dung from treated cattle. No differences were detected for other taxa. A change in cattle diet may have altered levels of faecal residues, thereby changing beetle preferences between years. Comparisons between periods of spring and autumn activity identified a change in seasonal preferences for at least some species. Similar numbers of Onthophagus nuchicornis Linnaeus and of A. fimetarius were collected in spring with dung from treated or untreated cattle, but significantly more individuals of both taxa were collected in autumn with dung from untreated cattle. In contrast, the preference of Aphodius prodromus Brahm for dung from treated cattle was unchanged between spring and autumn. These results show that ivermectin therapy does influence the colonization of dung from treated cattle. However, the nature of this influence is confounded by extraneous factors. Until such time that these factors can be accounted for, general predictions regarding the effect of ivermectin therapy on the colonization of dung by coprophilous insects are premature.
The effectiveness of exclusion barriers for polyphagous predatory arthropods in wheat
Authors: Holland J.M.
Published: July 2009

Vertical polythene exclusion barriers combined with trapping out using pitfall traps have been used to create enclosures within which arthropod numbers can be manipulated. This technique has been primarily used to investigate the impact of ground-dwelling polyphagous arthropods on cereal pests. Arthropod numbers in a total of 42 enclosed areas were compared to adjacent unenclosed areas over three years in Hampshire, UK. A range of arthropod monitoring techniques was used, including pitfall traps, fenced pitfall traps and D-vac suction samples. The enclosures were effective in reducing most species of Carabidae, Linyphiidae and Lycosidae encountered and numbers in pitfall traps were reduced by an average of 74%, 62% and 77% respectively. Similar reductions in densities of these taxa were found. Staphylinidae were less effected with an average reduction of only 32% in pitfall traps, although Philonthus species were reduced by 82%. Results were compared to previous studies.
Aphids on cabbage: tritrophic and selective insecticide interactions
Authors: Verkerk R.H.J. , Neugebauer K.R. , Ellis P.R. , Wright D.J.
Published: July 2009

Laboratory-based experiments are presented involving two aphid sepcies (Myzus persicae Sulzer, a generalist and Brevicoryne brassicae Linnaeus, a crucifer specialist), and the predatory gall midge, Aphidoletes aphidimyza Rondani, on three cultivars of common cabbage Brassica oleracea var. capitata cv. Derby Day (green-leaved), Minicole (green-leaved) and Ruby Ball (red-leaved). In a laboratory-based tritrophic system including both species of aphid, the three cabbage cultivars and A. aphidimyza, predator both species of aphid, the three feeding on M. persicae or B. brassicae on cv. Derby Day, while growth was slowest separate experiment, A. asphidimyza larva feeding on B. brassicae on each of the three cultivars were significantly smaller and consumed less aphid fresh weight when maintained outdoors (mean temperature = 13.5°C) compared with a constant environment room (20°C). However, in this latter experiment under neither regime were differeneces in predator growth or consumption significant between cultivars. Effects of selective insecticides (pirimicarb and a neem seed kernel extract, NeemAzal-T/SR) on bitrophic (aphid-host plant) interactions were also investigated in the laboratory. A pirimicarb dose equating to c. 15% of the recommended field concentration caused equivalent toxicity of M. persicae on cv. Minicole compared with aphids treated with a three-fold greater dose and reared on cv. Derby Day. Cultivar-mediated differences in aphid mortality caused by the neem extract when tested for systemic and translaminar activity were not apparent. The results are discussed in relation to ways in which host plant selection, selective insecticides and biological control could potentially be manipulated and optimized in aphid management system on brassica crops.
The potential for manipulating crop–pest–natural enemy interactions for improved insect pest management
Authors: Verkerk R.H.J. , Leather S.R. , Wright D.J.
Published: July 2009

This review identifies key ways in which manipulations of the crop environment based on detailed understanding of tritrophic interactions can contribute to improvements in the control of insect pests. Such approaches are likely to be of particular benefit against those pests, notably certain species of Lepidoptera and aphid, which are difficult to control with insecticides because of insecticide resistance or suppression of natural enemies. Particular attention is given to the compatibility (or otherwise) of partial plant resistance and biological control, citing examples which support contrasting tritrophic theories. Other areas considered and supported with examples include the use or effects of allelochemicals, refugia, intercropping, crop backgrounds, fertilization regimes, parasitoid conditioning (by host plants) and transgenic crops. Examples of manipulations involving use of selective insecticides which show compatibility with biological methods are also included owing to their possible suitability in integrated crop management programmes.
Genetic variability within and between English populations of the damson–hop aphid,Phorodon humuli(Hemiptera: Aphididae), with special reference to esterases associated with insecticide resistance
Authors: Loxdale H.D. , Brookes C.P. , Wynne I.R. , Clark S.J.
Published: July 2009

The damson–hop aphid,Phorodon humuli(Schrank), is a serious pest of hops in England. It is holocyclic (with obligatory sexual phase) and host alternating. From suction trap data,P. humuliaerial densities are known to be greatest in the main hop growing regions of Herefordshire and Kent (mid-west and south-east England, respectively), some 260 km apart. The aphid is now resistant to several insecticides. This is in part conferred by elevated carboxylesterase activity, ranging from low in susceptible to high in very resistant strains. Enzyme markers, including carboxylesterases (EST-4 to -7), separated electrophoretically from individual insects, have been used to examine the degree of genetic heterogeneity amongP. humulisub-populations on both its hosts –Prunusspp. (primary overwintering host) and hops,Humulus lupulus(secondary summer host). The esterase data revealed heterogeneity among subpopulations collected from wild, unsprayed hosts in regions less than 30 km in area, with a higher mean frequency of elevated esterase variants in the commercial hop growing regions of Herefordshire and Kent, compared with samples from a non-commercial region around Rothamsted. Esterase distributions remained similar over consecutive years. Similarly, allele and genotype frequencies for another enzyme (6-phosphogluconate dehydrogenase, 6-PGD) were also heterogeneous among subpopulations sampled at less than 30 km apart (especially fromPrunus) in each of the three regions surveyed, whilst allele and genotype frequencies sometimes remained stable over a number of summers. In addition, 6-PGD genotype frequencies were mostly congruent with Hardy-Weinberg expectations, even for parthenogenetically-reproducing aphids colonizing hops. These data suggest that the 6-PGD alleles tested are selectively neutral; that gene flow (=migration) is restricted between aphid populations, even within a single region (≤ 30 km) and, that the autumn migration from hops toPrunusis probably of shorter range (perhaps less than 20 km) compared with the spring migration fromPrunusto hops.
Evidence of density-dependent oviposition behaviour byListronotus bonariensis(Coleoptera: Curculionidae) in Canterbury pasture
Authors: McNeill M.R. , Baird D.B. , Goldson S.L.
Published: July 2009

Argentine stem weevil (Listronotus bonariensis) (Kuschel) is a pasture pest ofLoliumspp. in New Zealand and is the target of a classical biological control programme using the parasitoidMicroctonus hyperodaeLoan. However, laboratory experiments have indicated a strong density-dependent egg laying response which may have important implications for the biological control effort. Two field experiments were conducted using a manipulated range of weevil densities within 2.0–2.4 m–2field enclosures and oviposition activity measured by weekly sampling of grass tillers within the enclosures. In both experiments, density had no effect on general oviposition behaviour although the percentage of tillers found to be infested with eggs increased significantly at higher densities. In experiment 1,L. bonariensisexhibited strong density-dependent oviposition with a significant decline in eggs/tiller/female with increasing adult density. An initial population of fiveL. bonariensism−2oviposited 32 times more eggs/tiller/female than 200L. bonariensism−2. By comparison, density-dependent oviposition was absent in experiment 2 with eggs/tiller/female comparable for all densities. The dramatic difference between the two experiments in the expression of density-dependent oviposition was attributed to prevailing spring temperatures during the sampling interval, which in the second experiment were much cooler and delayed the onset of egg laying. It is probable that in experiment 2, oviposition was not regulated by density-dependent cues but limited by temperature and age related mortality in the adult population. The mechanism for density-dependent oviposition, its occurrence in the field and impact on the effectiveness of the parasitoidM. hyperodaeare discussed.
A preliminary survey of mitochondrial sequence variation in Triatominae (Hemiptera: Reduviidae) using polymerase chain reaction-based single strand conformational polymorphism (SSCP) analysis and direct sequencing
Authors: Stothard J. R. , Yamamoto Y. , Cherchi A. , Garcia A. L. , Valente S. A. S. , Schofield C. J. , Miles M. A.
Published: July 2009

Genetic variation within triatomine bugs was investigated by amplification of a 400 bp portion of the mitochondrial 16S ribosomal RNA gene by polymerase chain reaction (PCR), using evolutionarily conserved primers, from a selection of species representative of the genera Rhodnius, Triatoma and Panstrongylus. Amplification products were subsequently screened for sequence variation using single strand conformational polymorphism analysis (SSCP) and also subjected to direct sequencing. Single strand conformational polymorphism analysis could detect variation within and between genera; intraspecific variation was also detected and SSCP profiles appear to be useful for identification purposes at the inter- and intraspecific levels. A 290 bp multiple alignment of 15 sequences obtained from nine species was generated, phylogenetic inference subsequently used three methods; a distance estimate, maximum parsimony and maximum likelihood. This 16S region exhibited considerable variation which ranged from intergeneric to intraspecific levels. Phylogenies from these three methods of inference were in broad agreement. Triatoma and Panstrongylus were more closely related to each other than either was to Rhodnius, in keeping with the current taxonomic appraisal.
Descriptions of some African Eulophidae (Hym. Chalc.)
Authors: Ferrière Ch.
Published: July 2009

The family of the Eulophidae, which is probably the largest family of the Chalcidoidea, is still very little known, both systematically and biologically. Being small, they are often bred in large numbers from a single host and are thus of great economic importance, but not always useful, as many species are hyperparasites. The study of the African Eulophidae is still at its beginning, since only about 60 species are known, two-thirds of which have been described by Waterston and Silvestri. The Imperial Institute of Entomology has received and is receiving many species which still remain unnamed. Most of them belong to large genera, like Euplectrus, Pleurotropis, or Tetrastichus, which should be studied monographically. The six species described below have been chosen partly for their possible economic importance, partly because they are represented by series of males and females.
Some Forest Entomological Methods and Conceptions
Authors: Trägårdh Ivar , Butovitsch Viktor
Published: July 2009

During recent years in Sweden much time and work has been devoted to the devising of accurate and withal time-saving methods of estimating the number of bark-beetles breeding in a trunk as well as the total number of bark-beetles per hectare in a given instance. The results achieved by the methods finally adopted seem to us so satisfactory that we venture to think that the methods in question may be used to advantage even in other countries, when similar problems arise.
Three new injurious Curculionidae (Col.)
Authors: Marshall Guy A. K.
Published: July 2009

Protostrophus dianthi, sp. n.

♀. Black, with dense grey and pale brown scaling ; head brown with a grey stripe adjoining the eyes ; prothorax with a broad indefinite median brown stripe, the lateral areas grey with brown spots which sometimes form two narrow irregular stripes, the pleurae brown above and grey below ; elytra mottled with pale brown and grey, intervals 2, 5 and 6 usually with dark brown patches, the suture pale fulvous.
Notes on Blood-Sucking Flies in the Ilorin Province, Nigeria
Authors: Golding F. D.
Published: July 2009

The Nigerian Agricultural Department is endeavouring to find cattle with a sufficiently high degree of natural resistance to trypanosomiasis to enable them to be utilised for mixed farming in the Ilorin Province and elsewhere in the Middle Belt of Nigeria. In April 1935, a herd of West African Shorthorn cattle was obtained from the Gold Coast and these and other animals, purchased in Nigeria, were established at a central stock farm at Ilorin.
A Method for investigating Membrane Permeability
Authors: Brightwell S. T. P.
Published: July 2009

Recent developments of physiology have emphasised the importance of membranes, and in entomology, studies on the permeability of membranes would offer the necessary basis for investigations on the physiological action of insecticides, particularly those applied externally, as well as on the many aspects of insect physiology.
Notes on the Taxonomy and Synonymy of Zele, Curtis, and Macrocentrus, Curtis (Hym., Braconidae)
Authors: Nixon G. E. J.
Published: July 2009

This paper is the outcome of an attempt to identify certain species of Braconidae received from the Forest Research Institute, Dehra Dun. The material comprises parasites of various Lepidopterous pests defoliating teak, shisham and deodar. Three of them are dealt with in the following pages ; the others will be discussed in a later paper.
The Food and Feeding Habits of Antestia in Kenya
Authors: Le Pelley Richard H.
Published: July 2009

(1) Two host-plants of Antestia lineaticollis in addition to Coffea arabica are Psychotria nairobiensis and Pavetta elliottii.

(2) Laboratory experiments showed that red berries and large green berries are favoured foods, but feeding will also take place on small green berries, on shoots, and on leaves.

(3) Feeding trials showed that large green berry food is essential for normal length of life and normal egg production.

(4) Antestia was reared to adult stage when fed exclusively on large green berries, on small green berries, and on shoots, but not on red berries or leaves.

(5) In large green berries and small green berries the endosperm becomes infected with rots, usually caused by the fungi Nematospora coryli or Nematospora gossypii, which are introduced by Antestia, but in the case of ripe red berries the endocarp is seldom if ever pierced and rotting of the endosperm is not initiated at this stage.

(6) The amount of damage caused to the crop by rotting of the beans is related to the number of Antestia present, and a formula which is considered to represent this relationship is given. In practice as high a proportion as 97 per cent. of the beans have been found rotted when Antestia is numerous. The figures also show that even when Antestia population is low, an economically important amount of damage to the crop may occur.

(7) Antestia was proved to cause a dropping of young green berries. This seems not to be due to the insect feeding on the stalk, but to be a response by the plant to an interruption of normal growth of the bean due to insect feeding. A similar shedding has been noticed of berries damaged by other insects when it is known that no feeding on the stalk can have taken place.

(8) Feeding experiments in cages and sleeves showed that Antestia must rank as one of the important causes of the non-setting of flowers ; this form of damage has been neglected or minimised in the past.

(9) As a result of Antestia feeding on the growing point, leaves become scarred and distorted.

(10) A useful form of cage for experimental work of this kind is described.

(11) Definite confirmation was obtained that well-known abnormalities of the vegetative growth characterised by multiple branching are produced by the feeding of Antestia.

(12) It is shown that the growth is stopped or much reduced by the feeding of Antestia, and when this is associated, as it usually is, with multiple branching, a “ bunchy ” or “ matted ” growth results, which increases pruning costs and much reduces the cropping ability of the tree.

(13) A short discussion follows which indicates certain practical conclusions that can be drawn from the above results.
A Method of sampling Thrips Populations
Authors: Le Pelley Richard H.
Published: July 2009

For a study of population trends of Diarthrothrips coffeae, Williams, on coffee in Kenya, and to assess the value of sprays for its control, a method of sampling the population was required. This insect feeds on the leaves, green shoots, and berries ; but by far the greater part of the population lives on the leaves. Attempts to count the insects on the leaves in the field, by naked eye or with a hand lens, proved difficult and inaccurate. Two other methods were tried, those of E. A. McGregor (Pan-Pacif. Ent., 3, 1926, p. 29) and J. W. Evans (Bull. Ent. Res., 24, 1933, p. 349).The former proved unsatisfactory for several reasons such as the failure of the insects to forsake the leaves, the collection of debris on the grease tending to conceal insects, and the difficulty of counting the insects in the grease. The method of Evans was designed originally for obtaining the thrips from blossoms, but an examination of the method was made with the coffee thrips. Fairly consistent results were obtained with it, but the figures were low and it was clear that the sampling was not complete. It was found that a number of insects remained among the leaves and failed to reach the paper at the bottom of the cylinder. There are other disadvantages ; for example a large number of the cylinders are necessary to carry out a single spraying experiment, they are usually difficult to come by and the work of counting has to be done in the field, requiring a rather elaborate provision of tables and microscopes. Further it was found that even a light breeze was apt to cause loss of thrips during the counting.
“ Mosquitoes of the Ethiopian Region ”—Notes and Corrections
Authors: Hopkins G. H. E.
Published: July 2009

One or two errors in “ Mosquitoes of the Ethiopian Region ” have recently come to light, and several new Culicine larvae have been discovered since the first volume was published. I take this opportunity to correct the errors and to indicate the positions which the newly-described larvae should occupy in the keys. I have not seen most of these larvae and have inserted them in the keys solely from the descriptions.

A number of the mosquitos of which I described the larvae in Vol. I of the monograph were incorrectly determined, but Edwards has already pointed out these misdeterminations (in Vol. III) and I have not thought it necessary to mention them here.

At the request of Mrs. G. R. Cunningham van Someren (formerly Miss E. C. C. Macdonald), I have added her description and figure of the larva of Aëdes adersi and her description of that of Culex adersianus as an appendix (see p. 178).
Some Notes on the Integument of Insects in Relation to the Entry of Contact Insecticides
Authors: Wigglesworth V. B.
Published: July 2009

Insects immersed in oils exude minute droplets of water over the surface of the cuticle. These appear more rapidly in light oils than in heavy oils and are more numerous in young insects than in old. Immersed in mixtures of oils and alcohols which separate in contact with water they show a vigorous effervescence at those regions where the mixture penetrates most rapidly to the water in the cuticle. There is a delay of varying duration at different parts of the cuticle when heavy oils are used. This delay disappears if the lipoid layer is first extracted with petroleum ether.

Factors controlling the rate of entry of pyrethrum through the cuticle have been studied by the application of pyrethrum in oil to a restricted area of the abdomen of nymphs and adults of Rhodnius. Entry is more rapid in light than in heavy petroleum oils ; it is much accelerated if the cuticle is first treated with petroleum ether. Entry is very slow in vegetable oils. There are great individual variations, due chiefly to the thickness of the endocuticle, which in turn is determined by the size of meal taken before moulting, the age and the amount of food taken after moulting, and the degree of stretching of the cuticle. There is evidence that the pore canals are important in the passage of pyrethrum through the endocuticle.

Histological examination of the integument shows that in the nymph of Rhodnius oils are taken up first by the epidermal cells in the zone around the bristles ; later by the general epidermis. The uptake of oil is greatly increased if 5 per cent. of oleic acid is added to refined petroleum. In the adult Rhodnius soon after moulting, oils are taken up by the general epidermis. In old insects they are taken up solely by the dermal glands. There is no visible entry through the sockets of the bristles.

The entry of pyrethrum in oils is accelerated by the addition of oleic or other fatty acids.
Some Results of Studies on the Desert Locust (Schistocerca gregaria, Forsk.) in India
Authors: Ramchandra Rao Rao Bahadur Y.
Published: July 2009

[A voluminous general report on the organisation and the results of the locust investigations carried out in India in 1931–1938, under the auspices of the Imperial Council of Agricultural Research, was officially submitted to the Council by Rao Bahadur Y. Ramchandra Rao in 1941, but its publication has been postponed until after the war.

A copy of the report has been sent, by permission of the Council, to the Anti-Locust Research Centre at the Imperial Institute of Entomology, for information, and it proved to contain a wealth of data and of ideas, only some of which have been published in various preliminary papers by its author and by his colleagues. In view of the great scientific and practical value of the report, it appeared necessary to make at least its main findings available to other entomologists working on the subject, and permission has been obtained from the author and from the Imperial Council of Agricultural Research for the publication of some sections of the report. Only a few sections, selected and edited by Dr. B. P. Uvarov, are being published below, and it should be stressed that their publication in the abridged form does not in any way detract from the value of the complete report, which, it is hoped, will be published at the earliest opportunity for the benefit of all workers on the locust problem.]
Experiments on the Survival and Behaviour of the Itch Mite, Sarcoptes scabiei DeG. var. hominis
Authors: Mellanby Kenneth , Johnson C. G. , Bartley W. C. , Brown P.
Published: July 2009

(1) Adult female Sarcoptes were killed by 49°C. (120°F.) in 10 minutes and by 47·5°C. (117·5°F.) in 30 minutes.

(2) At 28°C. (82°F.) no Sarcoptes survived for two days and the majority died in 24 hours.

(3) At 13°C. (55°F.) and 90 per cent. R.H. the majority of the mites died within a week, but a few survived longer, even up to 14 days.

(4) At temperatures below 13°C. (55°F.) the mites survived for a shorter time.

(5) Sarcoptes gives no reactions, positive or negative to unidirectional light.

(6) Below 15°C. (59°F.) Sarcoptes is in chill coma. Little movement occurs below 20°C. (68°F.).

(7) In temperature gradient mites seldom, if ever, go below 24°C. (75°F.). They will walk into high temperatures which prove rapidly lethal.
The Emergence and Sex Ratio of Culex fatigans Wied. (Diptera, Culicidae) in Laboratory Experiments
Authors: Qutubuddin M.
Published: July 2009

In view of the great diversity of opinion on the subject of sex ratio and order of emergence of the two sexes of adults in laboratory-bred mosquitos and those occurring in nature, 70 experiments spread over a period of 1 year, were conducted in the laboratory at room temperature to study (a) the order of emergence of the sexes, (b) proportions of sexes in the total output in a brood, (c) the effect of larval and pupal mortality, (d) the effect of food, and (e) of temperature on sex ratio. The common species, C. fatigans, was chosen for the purpose.

By a statistical evaluation and graphical representation of the data it has been shown that males hatch out significantly earlier than females, and that the larval life of the males is significantly shorter than that of the females.

It is concluded that the sexes emerge in a 1: 1 ratio, although a small number of aberrant cases with a significant preponderance of one sex or the other may occur.

Larval as well as pupal mortality below 20 per cent. does not seem to affect the sex ratio; nor has it been possible to establish any relationship between sex ratio and mortality in any of the aquatic stages.
Flight in Desert Locusts in Relation to Humidity
Authors: Waloff Z.
Published: July 2009

An analysis of detailed observations on flying swarms of the Desert Locust,S. gregaria, on 33 occasions in eastern Africa has demonstrated an association of intermittent flight with higher and of continuous flight with lower saturation deficits. This association, which is consistent with recent laboratory studies on the effects of atmospheric humidity on the flight-performance of suspended locusts, is discussed in relation to the rate of movements of migrating swarms.
Studies of British Anthomyiid Flies
Authors: Miles Mary
Published: July 2009

The Spinach Stem FlyHylemyia echinata(Séguy), is an important pest of spinach (Spinacia oleracea) grown in the east and south-east of England for canning and freezing. Attack by the larvae results in the blackening and distortion of terminal shoots and the splitting and discoloration of petioles and mid-ribs, and some larvae may be present in the crops when they are harvested.

The eggs are laid in May on the upper surfaces of the leaves and among the leaflets of the terminal and axillary buds. The larvae penetrate the epidermis and tunnel through the mesophyll until they reach mid-ribs, petioles or stems where they feed on the hollow inner surfaces. The puparia are usually found in the soil but may occur in the feeding sites. The second generation emerges in June and July, and further emergences occur in August and September. Larvae are present in the crops from May to October.

Eggs and larvae are described and illustrated so that they can be distinguished from those of the Mangold Fly,Pegomyia betae(Curt.), which are often present on spinach at the same time. The flies are described and the characters which distinguish them from the Bean Seed Flies,Delia cilicrura(Rond.), are noted.
A Revision of the African Species of Sesamia Guenée and related Genera (Agrotidae-Lepidoptera)
Authors: Tams W. H. T. , Bowden J.
Published: July 2009

The primary object of the work which is the subject of this paper was to clarify the confusion that has existed for many years in the nomenclature and taxonomy of certain important Agrotid borers of graminaceous crops in Africa.

The genera involved are Spcia, Sciomesa, Poeonoma, Conicofrontia, Bussecla and Sesamia, and of these the first three are new and are described and the others are redescribed. A key to the genera and keys to the species of Sciomesa, Poeonoma and Sesamia are given. The genus Speia is erected for Phalaena vuteria Stoll; the name vuteria Stoll has been wrongly applied to the important pest of sugar-cane in Mauritius, which is, in fact, the well known Sesamia calamistis Hampson. Sciomesa is erected to contain three species previously included in Conicofrontia. Poeonoma also contains three species, of which one is Phragmatiphila serrata Hampson and the other two are new. Hampson's species Conicofrontia sesamoides is redescribed in Conicofrontia and is the only species of that genus dealt with in detail; Phragmatiphila bipartita Hampson is synonymised with it. In the genus Busseola, only the well known pest, B. fusca (Fuller) is described.
Some important Species of the Genus Cryptophlebia Walsingham, 1899, with Descriptions of three new Species (Lepidoptera: Olethreutidae)
Authors: Bradley J. D.
Published: July 2009

This work was undertaken to unravel past confusion concerning the identity of certain economically important species of Cryptophlebia. It involved the study of several other species of the same genus and has resulted in the recognition of three new species and the transfer to Cryptophlebia of several species hitherto placed in other genera, mainly Argyroploce.

The three new species are described and 14 species are redescribed. The distribution of each is given and the food-plants are listed where known. The adult female and the male and female genitalia of each of the new species and certain others are illustrated.