bluuebunny/crossref_metadata_2025_split huggingface dataset:
Natural Enemies of Sirex cyaneus, Fabr., in England and their Life-history
Authors: Chrystal R. N. , Myers J. G. 
Published: July 2009

Rhyssa persuasoria and Ibalia leucospoides, both parasitic on Sirex cyaneus, have been studied at Oxford.Rhyssa lays its eggs in the burrow of and near to the almost or quite full-fed host larva or the pupa, by piercing the solid wood with itsovipositor. Feeding is entirely ectoparasitic and takes only a few weeks, during which the host larva may burrow a little further. The winter is passed by Rhyssa as a resting larva. Pupation takes place in the spring, and the whole life-cycle normally occupies one year.Ibalia oviposits in the young larva just before ormore rarely just after hatching, utilising the oviposition-bores of the Sirex for this purpose. The first-stage larva is elongate, with sickle-shaped mandibles, and larval feeding seems wholly endoparasitic. Sirex larvae parasitised by Ibalia confine their boring largely to the outer portions of the trunk, and usually make their final cell just under and approximately parallel to the surface. The life-cycle of Ibalia requires at least two years.Owing to the very different instars which they attack, there seems no risk of superparasitism of Ibalia by Rhyssa or vice versa, and it is therefore suggested that both species be introduced into New Zealand as a measure against Sirex juvencus, which is there very destructive to plantations of Pinus radiata.
An Ecological Study of Mosquitos in Wuhan Area
Authors: Sheng Tseng , Wu I. 
Published: July 2009

Field and laboratory studies were made of the mosquitos of the Wuhan area, central China, between June 1947 and March 1948.The following species were collected :Anopheles hyrcanusvar.sinensis, Mansonia uniformis, Armigeres obturbans, Aëdes albopictus, Culex fuscanus, Culex vagans, Culex fatigans, Culex pipiensandCulex tritaeniorhynchus. A brief account is given of the topography and other environmental features of Wuhan.The seasonal incidence and feeding habits of the adults, and the breeding sites favoured by the various species are recorded.Monthly mean figures for rainfall, temperature and humidity are examined in relation to incidence of malaria and abundance of adults and larvae ofAnopheles hyrcanusvar.sinensis. The peak of malaria incidence coincides with that ofAnophelespopulation which occurs two to three months after the peak of rainfall at an average relative humidity of 66 per cent.A chemical analysis of waters from different types of breeding sites was made. Both the total organic nitrogen, and the amount of dissolved oxygen were considerably greater in the breeding site ofArmigeres obturbansthan in those of other genera. A sample of water from a site in which no mosquito breeding was observed contained very much smaller amounts of organic substances and minerals than samples from known breeding sites.Other ecological factors affecting the early stages in their breeding sites are briefly referred to.
Studies on Aqueous Suspensions of Insecticides. Part II. Quantitative Determinations of Weights of DDT picked up and retained
Authors: Barlow F. , Hadaway A. B. 
Published: July 2009

The weights of insecticide picked up by mosquitos and tsetse flies in short contact periods on deposits from aqueous suspensions of DDT crystals of different sizes have been determined chemically and correlated with corresponding mortality rates.The rate of action of DDT particles picked up by mosquitos increases as the size decreases.Taking into account the weights of insecticide picked up, the median lethal dosage increases as the particle size increases. A further factor, that of retention on the body of the insects, has to be considered, however, for there is evidence that adherence of particles in the 0–10 and 10–20 micron ranges is greater than that of larger particles. Availability, and therefore effectiveness, of deposits from aqueous suspensions of insecticide particles is influenced considerably by the type of material to which they are applied.
Diapause behaviour of Zygogramma bicolorata (Coleoptera: Chrysomelidae), a biological control agent for Parthenium hysterophorus (Asteraceae), in Bangalore, India
Authors: Jayanth K. P. , Bali Geetha 
Published: July 2009

AbstractZygogramma bicolorata Pallister was introduced for biological control trials against the weed Parthenium hysterophorus (Asteraceae) in India. The insect entered diapause over an extended period of time between July and December in Bangalore. Diapausing adults burrowed into the soil, and emerged in May–June with the commencement of monsoon rains. Percentage diapause increased over time, peaking at 72% during November. Non-diapausing adults were capable of breeding, under laboratory conditions, during the winter. Some adults bred both before and after diapause, during two consecutive years. Soil moisture played an important role in providing the conditions for burrowing or emerging from the diapause chambers. The studies also showed that diapausing adults had to be exposed to the high summer temperatures, for termination of the diapause. It was possible to break diapause by continuous exposure to 30°C, 35°C and 40°C for 22 days, nine days and 10 hours, respectively, during February–March, about three months after its inception. This method can be used to initiate mass multiplication for carrying out releases early in the season.
The early Stages of British Biting Midges Culicoides Latreille (Diptera: Ceratopogonidae) and allied Genera
Authors: Kettle D. S. , Lawson J. W. H. 
Published: July 2009

This paper presents a key to the larvae and pupae of 28 species of Culicoides found in Britain and to larvae and pupae of the genera Stilobezzia, Serromyia and Ceratopogon including the subgenera Ceratopogon and Isohelea. The keys are supplemented by descriptions of the larvae and pupae, including photographs of the fourth instars and figures of the so-called “hypopharynx” —the true epipharynx—of most of the larvae and by figures of specific characters of the pupae. Twenty-eight species of Culicoides larvae are described:—C. albicans, C. chiopterus, C. circumscriptus, C. cubitalis, C. cunctans, C. delta, C. fascipennis, C. grisescens, C. halophilus, C. heliophilus, C. impunctatus, C. lupicaris, C. maritimus, C. nubeculosus, C. obsoletus, C. odibilis, C. pcdlidicornis, C. pictipennis, C. pseudochiopterus, C. pulicaris, C. punctatus, C. riethi, C. salinarius, C. scoticus, C. simulator, C. stigma, C. truncorum, and C. vexans. The descriptions of the pupae include all the above, with the addition of C. parroti.An analysis has been made of the breeding preferences of Culicoides and it was found that species could be placed in one of six groups depending on the larval habitat. The six categories were:— (i) Bog, (ii) Fresh Water Marsh, (iii) Swamp, (iv) Mud, (v) Salt Water Marsh and (vi) Dung.The vertical distributions of seven species of Culicoides larvae are given. There are marked differences between the species in this respect.
The Effects of atmospheric Pressure on the Flight Responses of Aëdes aegypti (L.)
Authors: Haufe W. O. 
Published: July 2009

Laboratory investigations with the mosquito AËdes aegypti (L.) have shown that air pressure has the following effects on flight activity:The effects of pressure changes are consistently large enough to constitute an important factor in determining activity provided the mosquitos are acclimatised first to a particular pressure level.The period of constant conditions necessary for complete acclimatisation was between three and six hours for all pressure conditions investigated.When the period of acclimatisation had been fulfilled, the flight activity was approximately the same at all levels of static pressure investigated between 550 mm. and 800 mm. Hg.After complete acclimatisation the activity following a moderate decrease in pressure was 1·5 to 2·4 times that following a similar increase in pressure when the general pressure level exceeded 735 mm. Hg.When the general pressure level was less than 735 mm. Hg., the activity following a decrease in pressure was less than that following an increase; it would appear that 735 mm. is a critical pressure level for the stock of A. aegypti employed.The activity during a uniform rise in pressure from 530 mm. to 730 mm. at 7·7 mm. /min. was at least 10 times that during a reverse fall in pressure fall in pressure at the same uniform rate.Provided the rate of change was not greater than 1 mm./sec., the maximum flight activity for falling pressures was observed at 780 mm. while the maximumfor rising pressures was observed at 735 mm.
Aircraft Applications of Insecticides in East Africa. VIII.—An Experiment against the Tsetse Fly, Glossina swynnertoni Aust., in an isolated Area of Thronbush and Thicket
Authors: Hocking K. S. , Burnett G. F. , Sell R. C. 
Published: July 2009

An isolated area of 2,200 acres of thicket and thronbush in the Central Province, Tanganyika, was treated from the air with a DDT-in-oil aerosol in an attempt to eliminate the tsetse fly, Glossina swynnertoni Aust. Eight applications of 0·25 lb. technical DDT per acre were planned to be done at fortnightly intervals.Delays due to unseasonal bad weather reduced this to seven at a slightly higher rate and over a longer-period.G. swynnertoni was reduced from an apparent density of about 7 to zero at the end of the second application. No flies were caught after the fifth application for a period of six months.It is not possible to say whether the few caught since then have been brought in or are the offspring of survivors of the insecticidal treatment.This experiment was more successful than that on the Galapo Block in the same ares, to a highly significant degree, and this is attributed to the vulnerability of the smaller population present. It was doubtfully better than the first treatment of the North Block, also in this area, because the increase in population in the latter block may have been assisted by immigration.
Oxygen Absorption of Natural Waters in Nairobi with Reference to Anopheline Mosquitos
Authors: Harvey D. , Symes C. B. 
Published: July 2009

The following data have been gathered over a period of about one year (January to December 1929) in the Nairobi District, Kenya Colony.It was thought that the organic content of natural waters would certainly offer some indication of their suitability for the breeding of Anopheline mosquitos and that an investigation might suggest some definite line of approach to this intensely complex problem.During November and December 1928, certain water sources were selected by one of us (C. B. S.), in widely separated parts of the district, for weekly sampling. In each separate area some four to eight places were chosen for routine searches for Anopheline larvae ; thus in the Q area (Table II) seven places were searched every week and in the B area (Table I) six places. From the places in each area two were chosen for routine oxygen absorption tests, one with Anopheline larvae and one without, water from these same two places being sampled and tested weekly. Thus in the Q area, spots Q 5 and Q 6 were used for this purpose, and in the B area B 3 and B 5. It is necessary to emphasise the fact that these places were separated from one another by distances of 50 to 150 yards. The choice of the source of water to be sampled was made purely on the presence or absence of Anopheline larvae at the beginning of the work.
Phytalus (Col., Melol.) in Sugar-cane in Mauritius
Authors: d'Emmerez de Charmoy D. 
Published: July 2009

Like Mauritius, many other cane-growing countries in the world are suffering severely from the ravages of Lamellicorn beetle grubs. In some of these countries, such as Australia, India, South America and the West Indian Islands, these insects are indigenous, whilst in others, such as Hawaii and Mauritius, some of them have been accidentally introduced.Through intensive cultivation of sugar-cane, which in some places is the staple industry, these so-called white grubs have found an abundance of food and an adequate environment, so that they have become, even in their country of origin, a major pest of sugar-cane ; whilst in places where they have been introduced, the damage done, in some cases, is a serious menace to the sugar industry.Heavy annual losses are being sustained in the Philippines, Queensland and Porto Rico ; at present the damage in Porto Rico is estimated to be 3 million dollars yearly.In order to cope with such a state of affairs, all possible effort is nowadays being made in most of these countries to try to control the pests by rational and scientific methods. Though many important points have been solved by research workers engaged thereon, there still remain many unknown factors upon which enlightenment is required.
New Trypetidae (Dipt.) from South Africa, II
Authors: Munro H. K. 
Published: July 2009

The following descriptions axe based on material collected or reared by the author, together with specimens reared from host-plant material collected by colleagues to whom the author's thanks are due.From the descriptions it will be further evident that the generic location of new species is still difficult, but this state of affairs can only be remedied by a monographic revision of the African Trypetidae. It is felt, however, that although the author has such a work in progress, it is not desirable to hurry publication. Delay is advisable, especially in view of the number of new species continually being found, and the frequent need for the formation of new genera.Types of the new species are in the author's collection ; paratypes so far as available will be placed in the British Museum.
Further Studies on Leaf-curl of Cotton in the Sudan
Authors: Kirkpatrick T. W. 
Published: July 2009

The reasons for adopting the name “ leaf-curl ” for the virus disease which is manifested by symptoms of “ leaf-crinkle ” on certain varieties of cotton, and by “ mosaic ” on certain others, are discussed.A brief review is given of the very few references in previous literature which are relevant to leaf-curl.Up to the end of February 1931, 168 straightforward attempts had been made to transmit crinkle from Sakel cotton to Sakel by means of white-flies (Bemisia gossypiperda, Misra & Lamba), of which no fewer than 157 were successful. No transmission was obtained with any other insects.A single white-fly can transmit the disease to a healthy plant, though infection is less regularly obtained when one or only a few white-flies are used.There is a large amount of negative evidence which indicates that the virus is not transmitted through the seed of Sakel cotton. There is also no evidence that it can be transmitted through the soil.In nearly 200 controlled experiments, the incubation period of the virus in the plant varied from 8 to 34 days, but over two-thirds of the recorded periods were between 11 and 19 days. Possible causes of the variation in the incubation period are discussed.Little is known with certainty about the factors which influence the severity of the disease.At least one case of complete recovery from the disease appears to have been observed. Partial recovery is not infrequent.
Parasites and Hyperparasites of the Egg-pods of injurious Locusts (Acridodea) of Turkestan
Authors: Jazykov (Zakhvatkin) Al. A. 
Published: July 2009

The following brief contribution summarises a part of the contents of an extensive Russian report on parasites of the egg-pods of some Turkestan Acridodea, studied by the writer while on the staff of the Middle-Asian Institute of Plant Protection (Tashkent, U.S.S.R.), in the years 1927–30.The writer is specially indebted to Mr. V. I. Plotnikov, Director of the Institute, under whose supervision the work was done, and who kindly identified the Acridian hosts ; and for the identification of the parasites reared, to Messrs. A. A. Ogloblin, Santa-Anna (Scelionidae), S. J. Paramonov, Kiev (Bombyliidae), B. B. Rohdendorf, Leningrad (Tachinidae) and B. S. Kuzin, Moscow (Meloidae). The author's thanks are due also to Mr. B. P. Uvarov, for his kind assistance in the publication of this note.
The Eradication of Simulium neavei, Roubaud, from an Onchocerciasis Area in Kenya Colony
Authors: Garnham P. C. C. , McMahon J. P. 
Published: July 2009

1. An onchocerciasis area in South Kavirondo, Kenya Colony, 65 square miles in extent, has been freed from Simulium neavei.2. The fly was eliminated by the periodical application of DDT emulsion to all infested rivers and streams in the locality. Details of technique are described.3. Most aquatic life, other than this species of Simulium, had returned to the treated streams, three months after the last application.4. A microfilaria index of 37 per cent. in children aged four to eight was established as a base-line for future surveys.
Observations on Mortality among Insects exposed to dry insecticidal Films
Authors: Busvine J. R. , Barnes Sarah 
Published: July 2009

A variety of insects were exposed to films of insecticides by confining them for various periods on filter papers impregnated by a volatile solvent method. The following results were observed:—1. Nine species of insect and two species of tick were exposed to films of different insecticides for a standard exposure of two hours at 30°C. It was found that freshly prepared films of Gammexane were most toxic, followed by pyrethrins, DDT and rotenone.2. The relative toxicity of the films of undiluted insecticides is considerably different from that of the same insecticides applied in oily solution.3. The very sparse toxic films of Gammexane soon lost their toxicity, apparently by evaporation. The pyrethrin films were also less persistent than those of DDT.4. The test organisms can be arranged in groups showing different types of susceptibility.5. Percentage mortality among bugs kept in motion for a specified period over a given deposit of DDT is greater than that among stationary bugs exposed to the same deposit for the same period. The addition of an irritant to a DDT spray would therefore enhance the efficiency of the insecticide.6. A marked time lag in achieving complete mortality among bugs exposed to dry DDT films is recorded. No such lag was observed among bugs exposed to Gammexane nor among lice and flour beetles exposed to DDT. In these latter cases, percentage mortality gradually increased as the time of the exposure increased.7. Percentage mortality among bugs exposed intermittently to DDT for a given total period of exposure did not differ appreciably from that obtained among bugs exposed continuously for the same period. After intermittent exposure for a particular total time, the length of the intervals during which the insects were in contact with the insecticide did not influence the percentage mortality.
Initial Experiments in the use of DDT Against Mosquitos in British Guiana
Authors: Symes C. B. , Hadaway A. B. 
Published: July 2009

1. Simple trials of the effect on mosquitos of single applications of DDT to the internal surfaces of houses were initiated in British Guiana during the period 27th January to 20th April, 1945.2. The solution used in the first two trials was 4·6 per cent. DDT (72 per cent. para para) in kerosene applied at the rate of about 2 quarts per 1,000 square feet (i.e., approximately 100 mg. of crude DDT per square foot).3. An apparent reduction in the house population of Anopheles darlingi, the chief malaria vector, followed the treatment. Reduction exceeded 99·7 per cent. over eight weeks in the treated houses on one estate and 98·8 per cent. over six weeks on another.4. In a third trial with a small variety of simple formulations, promising results were obtained with a 6 per cent. emulsion and a 2½ per cent. solution. But mosquito catches over a short period suggest that mud walls, thatch and whitewash may interfere to some extent with the action of DDT.5. The cost of applications was of the order of one shilling and sixpence for each room (or small hut) of about 1,000 sq. feet internal wall and ceiling surface. This estimate does not include European supervision or the initial cost and depreciation of apparatus.
Studies of British Anthomyiid Flies
Authors: Miles Mary 
Published: July 2009

A study of the immature stages of the Anthomyiid flies, Delia cilicrura, D. trichodactyla, Erioischia brassicae, E. floralis and Pegohylemyia fugax, associated with injury to cruciferous crops, has shown that the several species can be distinguished. The egg stage can be identified by the sculpturing of the chorion, except in the case of the closely related species E. brassicae and E. floralis where the sculpturing is similar but there is a considerable difference in size.The larvae can be distinguished by differences in the shape and character of the head and in its relation to the prothorax, and in the form of the mouth-parts in the three instars. The number of finger-like processes of the anterior spiracles and the number and arrangement of the tubercles of the eighth abdominal segment also contribute to the identification of the larvae.
On the Parasites and Predators of the Cockroach. I.—Tetrastichus hagenowii(Ratz.)
Authors: Cameron Ewen 
Published: July 2009

In this paper the cockroach, a general name used here to include the commoner species ofPeriplaneta, BlattaandBlattella, etc., is approached from an economic and medical point of view. Special emphasis is placed on the possibilities of its control by biological methods, and to this end the whole field of its inter-relationships with other organisms in various parts of the world has been carefully surveyed. As a result some 73 parasites, predators and symbionts from such widely diverse groups as the Protozoa, Nematoda, Insecta, Arachnida, the Algae and Bacteria have been reviewed and classified.The more important parasites, some 25 in number, have been placed along with the chief predators in a group (A) by themselves. Most of the former are members of the Hymenoptera-Parasitica, the more prominent being the Eulophid,Tetrastichus hagenowii(Ratz.), and theEvaniid, Evania appendigasterL., with six of its congeners. Amongst the predators of this group, certain Sphecoid wasps of the genusAmpulex, represented by seven distinct species, take pride of place. In the second big division (B) the individual species are mostly members of the Protozoa, withEndamoebaas a prominent genus, and of the Nematoda, with several genera, most of them in the Oxyuroidea.The present paper, which is intended to serve as the introductory one of a series on the natural enemies of the cockroach, deals in detail with a very important parasite, namely the Eulophid,Tetrastichus hagenowii.
The Fertilisation ofGlossina palpalisin Captivity
Authors: Nash T. A. M. 
Published: July 2009

In breedingGlossina palpalis(R.-D.) in captivityin Northern Nigeria, it was found that even though the sexes are segregated within 24 hours of emergence, a few females succeed in producing larvae. Examination of the spermathecae of females thus segregated shows that nearly 4 per cent. are fertilised. This low fertilisation rate is due to the impotence of most males under 24 hours old. When young males of different ages were forced to compete with older males for the females' favours, it was found that young males must be 7 to 8 days old before their virility approaches that of older males.When virile males are added to mating cages containing virgin females, pairing startsimmediately, but the number of pairs decreases steadily until after 23 hours, pairing has virtually ceased. The cessation of copulation is due to the female becoming unwilling to pair and to her ability to repulse the male; but if she is re-fed her willingness will be restored to a considerable extent. There is no need to leave the sexes together formore than 24 hours, as excellent fertilisation can be achieved in that time.