bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stimuli involved in the Attraction of Aëdes aegypti, L., to Man
Authors: Parker Alec H. 
Published: July 2009

The reactions of Aëdes aegypti females to certain stimuli normally associated with the human surface body have been investigated. The apparatus used was such that the insects were unable to touch the source of stimulation. Attraction to the latter was indicated by the congregation of females in its vicinity.The following stimuli proved attractive: the intact palm of the hand; collected sweat at room temperature; moisture at room temperature; moisture at body-surface temperature. A warm surface at body-surface temperature produced no apparent effect, either of attraction or of repulsion.The four types of stimulus found to be attractive also had marked activating effects. The magnitude of these effects was much greater for the hand and warm moisture, than for cold sweat and cold moisture.Due allowance for the complication introduced by these differences in activation having been made, cold sweat appeared to be slightly, but significantly, more attractive than cold moisture. A reaction to olfactory stimuli is presumed to have been responsible for this. Such stimuli, however, are not considered to have been of much importance in comparison with warmth and moisture; moisture at body-surface temperature had very nearly, and possibly the same, attractive effect as the intact hand.The results are compared with those of other recent investigations, and the need for caution in applying them where conditions differ from those under which they were obtained is emphasised.
The Penetration of Insect Egg-shells
Authors: Beament J. W. L. 
Published: July 2009

During development, membranes are added to the inner surface of the chorion in eggs ofRhodnius prolixus. The chemistry and permeability of the membranes have been investigated.A true fertilisation membrane is produced immediately before oviposition when the egg is fertilised. It is attached to the inner surface of the primary wax layer, recessed into the micropylar region and covers the whole inner surface of the shell.The membrane is very thin when first formed. It is colourless, comparatively resistant to solvents and apparently composed of “vulcanised” protein. It is semi-permeable to salt solutions but made very permeable to small molecules when immersed in absolute alcohols.In the following five days of incubation, further material is added to the fertilisation membrane. Over the main part of the shell and cap, this does not cause a great increase in the thickness of the, membrane. The added material is probably proteinaceous, with tanning- and vulcanising substances and it is mostly a product of the serosa.Opposite the inner openings of the micropyles, material is accumulated at a much greater rate and by six days incubation the membrane may be fifteen microns thick. The inner surface of the egg-shell thus becomes a uniformly ellipsoidal body. The thickened material has been called the epembryonic ring.At about the, sixth day of incubation, shortly before blastokinesis, the membrane is partially impregnated with a high-melting-point wax. This raises the “transition point” in the egg's water-loss/temperature curve from 42·5°C. to 68°C. Evidence is against this material being arranged as a second wax layer on the inner surface of the membrane.No further changes were detected until the thirteenth day when the innermost part of the membranes are broken down by the embryo. On the day before eclosion the embryo is surrounded by a liquid containing emulsified wax and proteinaceous material. The properties of the membranes return towards those of the one-day-old egg but do not attain them ; the egg hatches on the 16th day.The changes in the membranes produce considerable changes in the apparent toxicity of ovicidal liquids; ovicidal experiments are recorded and explained. In general, the egg becomes more resistant to lipophiles over the first six days and less resistant afterwards, due to the wax impregnation. The resistance to hydrophiles increases during development due to the epembryonic layer and secondary wax, but decreases when the membranes are broken down just before eclosion.
The Parasites and Predators Of Potato Aphids
Authors: Dunn J. A. 
Published: July 2009

The parasites and predators found attacking the Aphids,Myzus persicae, Macrosiphum solanifoliiandAulacorthum solani, during field survey work of potato Aphids in the Northern Agricultural Advisory Province during 1944 and 1945, are treated individually, receiving the proportionate attention which their occurrence merits.Aphidius avenaewas the most important primary parasite, and in potato seed growing areas, the only one; whileAsaphes vulgarisin particular, augmented byLygocerus testaceimanuscomposed the majority of hyperparasites. The effect and relative importance of both types of parasite upon the Aphid populations of the survey are discussed with their percentage figures.Predacious Syrphids includedPlatychirus manicatusandP. immarginatuswhose life-histories were previously unknown; feeding records are also given for these two, and the former species accompanied invariably byP. scufatusoccurred regularly on potatoes. More unusually, but often more effectively,Syrphus balteatusappeared. Other species were found.
Studies on West African Forest Mosquitos.—Part I. The seasonal Distribution, biting Cycle and vertical Distribution of four of the principal Species
Authors: Mattingly P. F. 
Published: July 2009

The present paper is the first of two dealing with the seasonal distribution, hourly variation in biting activity, and vertical distribution of certain Southern Nigerian mosquitos. The technique employed in the studies under discussion resembled that used by Haddow (1947) in Uganda. Human bait was used in both cases and the agreement between the results obtained in the two localities is felt to be such as fully to justify the employment of such methods. Over fifty species of mosquitos were taken in all and fourteen of these proved to be sufficiently abundant to yield significant figures. Four of these are discussed and the remainder will be dealt with in the second paper.The most remarkable feature of the seasonal distribution was the very restricted period during which Anopheles gambiae was present in any abundance. This species occurred in large numbers only during the heavy rains of June and July and, to a less extent, in association with the small rains of September–October. During the dry season it almost disappeared. Aëedes africanus showed a similar distribution to that of gambiae but Taeniorhynchus africanus and Anopheles hargreavesi were most numerous during the dry season. It is suggested that in the area under consideration the latter species may well be a more important malaria vector than gambiae owing to its greater abundance and more uniform seasonal distribution.
Observations on the Control of Kenya Coast Glossina
Authors: Moggridge J. Y. 
Published: July 2009

A small reclamation experiment staged in the coral rag thicket under unfavourable conditions proved successful in eradicating Glossina austeni and G. brevipalpis and in virtually eradicating G. pallidipes. Applied with adequate protective clearings, it is thought that the method may prove entirely successful in eradicating G. pallidipes as well as G. austeni and G. brevipalpis.Under both dry and wet season conditions traps proved quite ineffective.
The Duration of the Aquatic Stages of Anopheles minimus, Theo., determined by a new Method
Authors: Ribbands C. R. 
Published: July 2009

A new method of determining the duration of the aquatic stages of Anophelines in nature is described. Repeated daily dippings of a stretch of stream were made, and the numbers of pupae and of larvae of each instar were recorded. The duration of the aquatic stages was then determined by analysis of the sequences of peaks in these numbers.The duration of larval life of A. minimus, when living in a stream at an average daily range of water temperature between 26·5°C. and 30·6°C, was seven days.The full life cycle of A. minimus, under monsoon conditions in Assam, probably occupied 14 days—egg 2 days, larva 7 days, pupa 2 days, adult to first egg-laying 3 days.
A revised Key to the Larvae of the Ptinidae associated with Stored Products
Authors: Hall D. W. , Howe R. W. 
Published: July 2009

During the past 12 years, records of beetles of the family Ptinidae as pests of stored products in Britain have been increasing in frequency. Kloet & Hincks (1945) record 21 British species of Ptinids, but of these, three species, Ptinus palliatus, Perris, P. pilosus Mueller and P. latefasciatus Gorh., have not so far been recorded from warehouses or stored products and a furthertwo species, P. lichenum Marsh. and P. subpilosus Sturm have only rarely been recorded from such habitats. The importance of birds' nests as reservoirs of pests of stored products is being shown in a paper to be published shortly by Woodroffe and Southgate who carried out a survey of the fauna of the nests of birds associated with buildings. They found that the fauna of such a habitat was extraordinarily similar to that of warehouses in this country and that very large numbers of several species of Ptinids were present. The risk of this habitat being a possible source of many Ptinid infestations can be gleaned from the following list of species which they found:—Ptinus tectus Boield., P. fur (L.), P. sexpunctatus Panz., P. pusillus Sturm, P. subpilosus Sturm, Eurostus hilleri (Reitt.), Niptus hololeucus (Fald.), Mezium affine Boield., Trigonogenius globulus Sol.
On Swarming and Mating in Anopheles aquasalis Curry
Authors: Senior white R. A. , Lewis G. , Lee P. 
Published: July 2009

In Trinidad A. aquasalis swarms over open areas, mostly grass, and over drains and not over scrub vegetation.Swarming commences at a light incidence not exceeding 5 foot,-candles.Mating has been observed in 54 per cent. of the swarms, the fertilisation index of females captured in them being 65 per cent.The lag between the first sight of a swarm and the first observation of a mating pairaverages 6·5 minutes, the light incidence at commencement of mating being no higher than an average of 0·8 foot-candles.
Observations on the Entry of Dusts into the Respiratory System of the Adult Worker Honey Bee, Apis mellifera L.
Authors: Connell Joan U. , Jones G. D. Glynne 
Published: July 2009

A description is given of the hair structures associated with the spiracles of the adult worker honey bee, Apis mellifera L.The surface hairs around the spiracular orifices vary in size, density and arrangement and with the exception of those of the third, fifth and sixth abdominal spiracles appear to be capable of holding back particles greater than 30 microns.When living bees were exposed to dust clouds of charcoal and cuprous cyanide, no particles were found in any internal part of the respiratory system beyond the spiracles except in the case of the trachea of the first thoracic spiracle which contained charcoal particles less than 5 microns.The mechanism of tracheal ventilation was considered and evidence accumulated to suggest that all spiracles could have an inspiratory function.
Formation of Green Pigment and Colour Changes in Orthoptera
Authors: Okay Salâhattin 
Published: July 2009

The colour change and formation of green pigment inMantis, Acrida, Locusta, SchistocercaandDixippusare studied.There is no background reaction to green and brown or yellow colour in these species.Usually the young nymphs ofMantisare green; some ofthe old nymphs and adults have a tendency to lose the green pigment. Phytophagous nymphsbecome green only when fed on fresh or growing grass. Green individuals may be obtained in darkness on this food (Locusta). The green pigmentdisappears on a diet of dry grass.The colour change from non-green to green, orvice versa, is dependent on the formation or disappearance of the blue component (bile pigment-protein) of green pigment. The blue pigment generally appears first in the blood and is deposited in the integument at the following moult; it does not appear to be a breakdown product of chlorophyll or haematin. It is probably synthesised from a colourless precursor in the peripheral fat body.Observations made on the pericardial cells ofLocustasuggest that the blue pigment may be converted into insectorubin.
On a Bostrychid Wood-borer in the Sudan
Authors: Peake F. G. G. 
Published: July 2009

Sinoxylon senegalense is essentially the wood borer of felled Acacia seyal Del. in the Sudan, damage due to other beetles being contributory in a very small degree.The life-history of the Bostrychid is recorded. The period from egg to adult is about eight weeks, but the complete life-cycle is considerably longer. The larval tunnels are superficial and only a few inches in length. The damage is almost entirely due to the adult, which remains boring within the logs for nearly 10 months. A predacious Clerid, Cylidrus fasciatus, and Braconid parasites, a species belonging to genus near Doryctes and Platyspathius pictipennis, were recorded.Destruction of the timber is very rapid and control methods should be undertaken as soon after felling as possible. Insectaries were prepared containing the timber treated in various ways and the behaviour of the insect noted in each instance. The chemicals used in the experiments were sodium arsenite, boracic acid and pentachlorophenol. The latter, used as a spray on barked logs, was found to be the most effective.
A Grouping by Larval Characters of some Species of the Genus Apanteles (Hymenoptera: Braconidae)
Authors: Short J. R. T. 
Published: July 2009

The larval characters of 33 species (largely Palaearctic) of the genus Apanteles have been examined and studied in relation to the division of the species of the genus into four major groups on the characters of the adults. Ingeneral, the larval characters indicate a grouping of the species which is very similar to the grouping of the adults. Groups S and U contrast sharply with groups A and F on the form of the mandible. The form of the mandible also allows group A to be distinguishedfrom group F. The relationships of four aberrant and some other species are discussed.I wish to thank Mr. J. F. Perkins of the British Museum (Natural History) and Professor G. C. Varley of the Hope Department of Entomology, Oxford, for permission to study material. Mr. G. E. J. Nixon's advice on the relationships indicated by the characters of the adults of the species of the genus Apanteles has been invaluable.
Studies of Lygus vosseleri Popp. (Heteroptera, Miridae), a Pest of cultivated Cotton in East and Central Africa
Authors: Geering Q. A. 
Published: July 2009

Methods have been developed for breeding continuous supplies of Lygus vosseleri in the laboratory. Adults readily oviposit in cotton seedlings, but tend to damage the tissues by feeding, so that the eggs fail to hatch. Portions of developing sorghum heads were found more satisfactory; grains in the milk stage stay fresh long enough for eggs laid in them to hatch, if the ratio of adults to grains is kept low.The method used was to expose sorghum grains to adult Lygus for 3–4 days, afterwards removing the grains to hatching cages to await emergence of nymphs. On emergence, nymphs were transferred to rearing cages and fed immature sorghum grains, changed every two days. Hatching and rearing cages consisted of muslintopped, celluloid cylinders fitting on to shallow tins containing moist vermiculite covered by plaster of paris in which small holes received the sorghum stems.At insectary temperatures the incubation period averaged 8·4 and the nymphal life 16·7 days; adult females survived up to 57 days and production of nymphs per female per day ranged up to 2·95. The mortalty in the egg stage is not yet known:the growth of fungi on the sorghum grains during incubation causes losses. Mortality in the nymphal stages averaged 44 per cent. and occurred chiefly in the first stage, probably due to handling. Improvements to reduce losses are described.Difficulties in maintaining continuous supplies of sorghum grains, caused by attacks of Atherigona on sorghum seedlings and of Contarinia on sorghum heads, can be overcome, respectively by the use of insecticides and by bagging the emerging heads.
The Sorghum Midge, Contarinia sorghicola (Coq.), in East Africa
Authors: Geering Q. A. 
Published: July 2009

Contarinia sorghicola was discovered in Uganda in 1951, the only previous African record being from the Sudan. The infestation started in September in early varieties of sorghum grown in observation plots and reached a peak onlate varieties and ratoons in early March, thereafter declining as parasitism, chiefly by Tetrastichus sp. and Aprostocetus sp., increased to reach 100 per cent. in April.The life-cycle was normally 19–25 days, but between December and April diapause larvae were found; these all produced adults in early August, following a period of high humidity.Midges morphologically indistinguishable from C. sorghicola have been bred from Eleusine coracana and from wild Sorghum verticilliflorum in Uganda, and the midge may well be endemic wherever wild sorghums grow. Enquiries show that midge damage to sorghum occurs in Kenya, Tanganyika and Nyasaland, and it is likely that all the mainsorghum growing areas of Africa will prove to be infested.The possible occurrence of resistance is discussed.
The Potency and Persistence of some new Synthetic Insecticides
Authors: Busvine J. R. , Nash Ruth 
Published: July 2009

Simple laboratory methods are described for assessing the potency and persistence of insecticides. Some of the newer synthetic insecticides have been tested by these methods against seven arthropod pests of medical importance.Initial potency was judged by the mortality of insects exposed to standard films of oil solutions of the compounds, on filter papers. The approximate order of potency of the samples tested was:—γBHC>dieldrin>aldrin=pyrethrins>chlordane=DDT= “Pyrolan” =allethrin> toxaphene.Residual action was judged by the mortality of batches of bed bugs exposed to films of the insecticides, at intervals up to six months after preparation. The approximate order of persistence was:—dieldrin=DDT=toxaphene>“Pyrolan”>γBHC=chlordane=aldrin>allethrin, pyrethrins.
Laboratory and Field Trials in the Control of Fleas and Lice
Authors: Shawarby A. A. 
Published: July 2009

The median lethal concentrations of some persistent insecticides as obtained by a filter-paper-impregnation technique for X. cheopis and P. humanus corporis are given. Their relative toxicity runs in the following order:—Flea (adults): Gamma BHC > dieldrin > aldrin > chlordane > DDT > pyrethrins > allethrin > toxaphene.Lice: Dieldrin > gamma BHC > aldrin > chlordane > pyrethrins > allethrin > DDT=toxaphene.On flea larvae gamma BHC is 36 times as toxic as p,p'DDT.On flea pupae gamma BHC and DDT powders and wettable suspensions are effective; further tests are required to determine their comparative toxicity.On mud blocks (London soil) gamma BHC wettable suspension is only 3 times as toxic as DDT compared with 20 times on filter papers impregnated with oil solutions. This is probably due to the more rapid sorption of gamma BHC as well as the difference of surface and formulation.In the field, at dosages of 2 gr. per m2 of 70 per cent. p,p′ DDT and i43 mg. of gamma BHC from wettable powders, BHC was superior to DDT as it gave a much better control of fleas (P. irritans) over the period of the experiment (24 weeks).Field trials on body lice by dusting the clothes, while worn, with 40 gr. (per person) of dusts containing, respectively, 10 per cent. (70 per cent. p,p′) DDT dust and 0·4 per cent, gamma BHC, showed that BHC gave more satisfactory results than DDT.The resistance of lice to DDT shown by Busvine in the local strain of Pediculus and the possibility of its occurrence among fleas may be one of the factors contributing to a better control by BHC.It was found possible to develop artificially, by selection in the laboratory, a slight degree of resistance in X. cheopis.
Selection of a BHC-resistant Strain of Drosophila melanogaster Mg
Authors: Oppenoorth F. J. , Dresden D. 
Published: July 2009

Two wild strains of Drosophila and one laboratory strain were selected for resistance to γBHC by a contact method. From each of these three strains equally resistant strains developed in about the same time. They did not become more resistant after prolonged selection. The resistance obtained was further investigated in one of the strains.There was no evidence of any specificity: the susceptibility of the resistant insects to DDT and “Thanite” also appeared to be less than that of the original strains.Although the strains were selected by a contact method they also showed decreased susceptiblity when the poison was applied to the skin and when it was injected. From the reciprocal crosses F1's were obtained the susceptibilities of which were practically the same and differed little from that of the resistant parent strain. It follows that resistance does not depend on cytoplasmatic heredity and that it is incompletely dominant.
Preliminary Tests of DDT Emulsion Concentrates
Authors: Jones B. M. 
Published: July 2009

A method for testing the physical stability of emulsions is described.Since the persistent toxicity of residual films is so important in the control of mosquitos and flies, this biological activity of stable DDT emulsions was measured by the response and susceptibility of Armigeres obturbans and Culex gelidus over a protracted period of time.These discriminating tests were carried out before emulsion concentrates were tried out in the field.
Equipment and Method employed in breeding Aëdes aegypti, L., for the biological Assay of Insecticides
Authors: David W. A. L. , Bracey P. , Harvey A. 
Published: July 2009

A method of rearing large numbers of Aëdes aegypti for the biological assay of insecticides is described. The larval food found to be most satisfactory was a breadcrumb infusion. Blood is necessary for oviposition (human blood is best), but the main batches of insects destined for spraying are fed on water, sugar and raisins.This work is being carried out under a grant from the Medical Research Council. The authors are grateful to Prof. P. A. Buxton and Dr. V. B. Wigglesworth for advice and encouragement.
Physiological and ecological Studies on the Species of Capnodis in Palestine (Col., Buprestidae)
Authors: Rivnay E. 
Published: July 2009

The economic importance of Capnodis in Palestine is discussed; the various species and their hosts are enumerated.The egg is described and its shell chemically analysed. It was found that potassium, calcium and magnesium are present as cations and chloride and carbonate as anions.The effects of relative humidity upon the egg are discussed. It is pointed out that the egg is resistant to a low percentage, but succumbs to a high percentage of relative humidity. The rôle of the egg shell in this matter is important.The effects of the temperature upon the eggs are discussed. Their development at various temperatures is calculated, and the Blunck formula applied. The mortality of the egg at high and low temperatures is shown in tables.