bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Stability of a DDT Suspension
Authors: Hawkins W. B. , Kearns C. W. 
Published: July 2009

A DDT sol, prepared in glass dishes in the manner described, has a reproducible zeta potential of −25 mv. Electrophoretic measurements showed that DDT conditioned in cardboard cartons has a zeta potential of zero.The zeta potential of the suspension behaves in a predictable and measurable manner in the presence of mono-, di-, tri-, and tetravalent ions.Spectrographic analyses showed that there are two identifiable sources of ions: (1) the DDT, and (2) the cardboard container. A third source of ions was indicated as being, singly or together, the distilled water and/or the DDT solvent.Spectrographic data showed that ions were associated with the conditioned DDT.In glass containers, a poor source of ions, kill of larvae of Anopheles quadrimaculatus Say was higher than in paper containers, a good source of ions. These data are correlated with the zeta potential and flocculation behaviour of DDT suspensions.
A Study of Factors determining the Distribution of the Larvae of the Blackfly,Simulium ornatumMg
Authors: Phillipson J. 
Published: July 2009

Field and laboratory studies on the rôle of oxygen concentration and speed of current on larvae ofSimulium ornatumMg. show that current speed is more important than oxygen concentration in governing their distribution.The larvae prefer waters with a velocity range of 50 to 120 cm./sec., the greatest numbers occurring between 80 and 90 cm./sec.Larvae move independently of oxygen in concentrations above 50 per cent, saturation level.
The Identity of Some East African Species of Saissetia (Homoptera, Coccidae)
Authors: De Lotto G. 
Published: July 2009

A systematic review of some species of the Coccid genus Saissetia occurring in East Africa led to the rediscovery of two species—S. persimilis (Newst.) and S. somereni (Newst.)—which although of economic importance have been almost completely neglected since they were first described. Both are redescribed in this paper. One new species recently collected in Kenya is described; this is S. pterolobina.Seven species are dealt with in the paper, including the important and widely distributed S. oleae (Bern.). A provisional key for their separation is included, while one species—S. cuneiformis Leonardi—is sunk as a synonym of S. nigra (Nietn.).
The Larvae of the Species of Tineidae of Economic Importance
Authors: Hinton H. E. 
Published: July 2009

Keys are provided for the larvae of 32 species of TINEIDAE, and detailed descriptions are given of 31 species. These include most of the species known to be of any economic importance. What is known of the biology of each is briefly summarised, but no attempt has been made to collate the available information on control measures.No larvae have been available of four species of some economic importance nor of twelve others of doubtful status as pests. The literature on each of these species is noted.The larvae of a few species of no known economic importance are described and are included in the keys. Most of these are very closely related to species known to be pests.The keys and descriptions include 21 species which are indigenous to Britain or are established here, so that keys and descriptions are now provided for half of the British species ofTineidae.
The Biology and Control of the Sugar-cane Chafer Beetles in Tanganyika
Authors: Jepson W. F. 
Published: July 2009

The principal pest of sugar-cane in northern Tanganyika is the Red Cane Beetle, Cochliotis melolonthoides (Gerst.) (Melolonthidae). Descriptions of adults and larvae of Cochliotis and of allied beetles found in the same area are given.The bionomics of Cochliotis have been studied in the field over two seasons. The life-cycle is annual with adult swarming in early October and a season of maximum larval damage in July–August.The intensity of infestation and the nature of the losses are discussed, and the mortality factors which act upon Cochliotis in nature are reviewed.Cultural control measures suggested include the deferment of planting until July to October, when larval activity has waned; introduction of quick-maturing varieties, mechanically cultivated so that long ratooning can be gradually eliminated; regulation of the water table by control of irrigation, and the trial of resistant varieties. The Mauritius varieties M. 134/32 and M. 165/38 are suggested in this connection.Biological control is discussed and a review of the parasite species that might possibly be introduced is made largely from the writer's Mauritius work on Clemora smithi (Arr.).Experiments in the chemical control of Cochliotis are described and the final recommendation is the application at planting of ½ lb. per 50 ft. of furrow of a BHC powder containing 2·5 per cent, of γ BHC. This practice has been adopted by the infested estate with successful results in virgins and first ratoons.Further work is suggested on the chemical protection of second and later ratoons by surface application of BHC or aldrin.
New Species of African Stem-boring Agrotidae (Lepidoptera)
Authors: Bowden J. 
Published: July 2009

Six new species of stem-boring AGROTIDAE are described from Africa. The new genera, Carelis, Poecopa and Manga are erected to accommodate three of these species; the other three species are described in the genus Busseola.A key to nine genera is given, and also one to separate five extremely similar species, Poeonoma serrata (Hampson), B. fusca (Fuller), B. quadrata, sp. n., B. phaia, sp. n., and B. segeta, sp. n.
The Mosquitos of Liberia (Diptera: Culicidae), a general Survey
Authors: Peters W. 
Published: July 2009

The results of a general mosquito survey of the Liberian hinterland are presented together with the findings of previous workers in this country.Liberia is almost entirely in the Upper Guinean Forest region with an annual rainfall from over 140 in. on the coast to about 80 in. in the hinterland.A list is given of all species recorded from Liberia.A brief account is given of the distribution, bionomics and relation to malaria of the Anophelini, with some taxonomie notes. Thirteen species or forms of Anophelines are listed, of which ten were found in the hinterland as well as on the coast.A summary of the distribution and bionomics of the Megarhinini and Culicini of Liberia is given, with the writer's field notes and those of earlier workers, and some taxonomic notes. Seventy one or 72 species or forms are included, of which 59 were found in the hinterland. If the first mention of some species in the two previous papers in this series be included, 41 additions to the Liberian list, three of them new species, have been made.
The geographical Distribution of Blowflies in Great Britain
Authors: MacLeod John , Donnelly Joseph 
Published: July 2009

The distribution in Britain of carrion-attracted Calliphorinae was examined by simultaneous trappings, under standard conditions, at 51 stations so distributed as to be more or less representative of the country.From published records and other sources, the known distribution of each species by vice-counties was delimited and compared with the observed results.Lucilia sericata (Mg.), L. caesar (L.), Calliphora erythrocephala (Mg.) and C. vomitoria (L.) are generally distributed. L. illustris (Mg.) is more widely distributed than was recognised, and is probably general, though relatively uncommon in hill country. Phormia terraenovae R.-D. and Cynomyia, mortuorum (L.) are also general, though more common in the north. The decrease in frequency southwards is more pronounced with C. mortuorum. and both species occur only rarely in Wales. L. silvarum (Mg.), believed previously to be confined to England, is also possibly generally distributed; it was trapped as far north as Caithness. It is uncommon north of the Highland Line.Lucilia ampullacea Villen., for which known records are restricted to south of the Humber-Mersey line, appears similarly to be almost general; it was taken both in hill and plains country up to the Inverness region.Of the remaining species that show some degree of geographical limitation, Acrophaga subalpina (Ringdahl) is the most widely distributed. It occurs at least as far north as the Inverness region, and south to the Severn-Wash line.The only Lucilia species with clearly restricted distribution is L. richardsi Collin. Its known territory was England south of the Pennines; this has now been extended into Wales and north to Cumberland and Durham, with one isolated record for the north-east of Scotland.Calliphora loewi End., believed a northern species, was taken throughout Scotland and northern England. C. uralensis Villen. is restricted to the northwest, and the Western Isles.Brief notes are given of the habitat preferences and seasonal distribution of the species.
Aircraft Applications of Insecticides in East Africa. XI.—Applications of a coarse Aerosol to control Glossina morsitans Westw. At Urambo, Tanganyika, and G. morsitans Westw. and G. pallidipes Aust. In Lango County, Uganda
Authors: Hocking K. S. , Yeo D. 
Published: July 2009

Two experiments are described where applications of coarse aerosols have been made to areas of savannah woodland infested with tsetse flies (Glossina spp.).The applications were made at nominal dosages of 0·25 gallons per acre, which was equivalent to either 0·20 lb. of p.p′DDT per acre, or 0·03 lb. of γ BHC per acre. The coarse aerosols had mass median diameters of approximately 60 microns.In one experiment, carried out at Urambo, Tanganyika, a reduction of 95 per cent, was obtained in populations of G. morsitans Westw. This kill was somewhat lower than in many other experiments, a fact that can be attributed mainly to our inability to maintain the cycle of applications. Immigration of flies into the treated area caused a relatively rapid increase in fly numbers to levels comparable to the pre-treatment populations, and in this respect the experiment was a failure.The other experiment, in Lango County, Uganda, was highly successful, and reduced a population of G. morsitans to 0·05 per cent, of its pre-treatment level, and eradicated a small population of G. pallidipes Aust. It is indeed likely that no stable population now exists in the area, and that the very few flies caught there since the end of the applications have been wanderers from other infested woodland. The continued success of the experiment is considered to be due to the effective isolation of the area.Some brief comments are made upon the costs of the method, and on its value under conditions of land development in Africa.
A diurnal Rhythm in the Emergence of Pegomyia Betae Curtis from the Puparium
Authors: Dunning R. A. 
Published: July 2009

There is a clear diurnal rhythm in the emergence of the Beet Fly, Pegomyia betae (Curt.), from the soil, peak emergence occurring daily between 06. and 07. hr., when the soil temperature at a depth of 2 in. and the air temperature are at about their minimum, or are just beginning to rise, and humidity is at its maximum. In two observations on the emergence of the first generation, 82·2 and 85·6 per cent, of the daily emergence occurred before 08. hr., whilst in two observations on the emergence of the adults of the non-diapausing part of the second generation, 79·1 and 76·3 per cent, of the daily emergence occurred before 08. hr.During the period of emergence of flies from a batch of puparia, the rhythm was most marked at the time of peak emergence, and was less marked at the beginning and end of the emergence period.The rhythm of emergence was much less pronounced, and the peak occurred later in the day, when puparia were kept at constant temperature from two days before the first flies emerged.Experiments led to the conclusion that the fly reaches the soil surface within one hour of leaving the puparium at a depth of 2 in. in soil, and that the processes of wing expansion and cuticle tanning are probably controlled by a nervous mechanism.The possible initiators of the diurnal rhythm are discussed. It is concluded that the results obtained could be explained by the suggestion that the rhythm is induced by the effect of temperature or light fluctuation at some time before the late pupal stage, or that it might be inborn in the species, and that it is further regulated by temperature variation at the time of emergence. Further work will be necessary before the suggested explanation can be shown to be valid or otherwise.
The Occurrence and Distribution ofAphomia gularis(Zell.) (Lep., Galleriidae), A Pest of Stored Products
Authors: Smith K. G. 
Published: July 2009

A summary is made of the literature dealing with the bionomics ofAphomia gularis(Zell.), a storage pest of almonds, walnuts, groundnuts and prunes, and to a lesser extent of rice and grain. Additional information is also given on its habits and occurrence in Britain.An outline is given of its origins, introduction and establishment in various parts of the world. The evidence leaves little doubt that the species originated in south-east Asia, its occurrence elsewhere being, with few exceptions, confined to the major ports of western Europe and North America. Cases of the spread of the pest from south-east Asia can be traced to the export of infested goods from that area. Unless action is taken to prevent further dispersal and measures applied to wipe out the known centres of infestation, further establishment of this species can be expected in countries at present not affected.It would appear thatA. gularisis a subtropical and warm-temperate species, rarely found in the tropics and only able to maintain itself towards the northerly limits of its range, as in northern Britain and Sweden, in heated premises. In the cooler temperate regions, such as Britain, it cannot compete with such species asEphestia elutella(Hb.) while in the tropics its ecological niche is filled by the very closely related speciesCorcyra cephalonica(Stnt.).Its apparent absence from regions in the southern hemisphere, where conditions favourable for development exist, may be due to its presence not having yet been recognised.
An Investigation of the Possibilities of Biological Control ofMelittomma insulareFairm. (Coleoptera, Lymexylonidae), a serious Pest of Coconut in the Seychelles
Authors: Simmonds F. J. 
Published: July 2009

The biology and general ecology ofMelittomma insulareFairm. in the Seychelles is briefly described and the difficulties in the biological control of this pest are stressed.As much information as possible was obtained concerning the species of the little-known family Lymexylonidae, particularly with regard to their biology, which in most cases has not been investigated. Several species might warrant further investigation with a view to providing natural enemies for use againstM. insulare, but in general what is known of their biology does not afford much hope that an effective parasite or predator will be found.The biology ofAtractocerus brasiliensisLep. & Serv. was investigated in detail in Trinidad but no natural enemy was found.The only possibility is thatRhizophagus dispar(Payk.), recorded as attackingHylecoetus dermestoides(L.) in England, might also attack the eggs ofM. insulare.
Mandibular Length in Nupserha bicolor Thoms. ssp. postbrunnea Breun. (Col., Lamiidae) as the Factor in determining the Site of Oviposition in Corchorus olitorius
Authors: Dutt N. 
Published: July 2009

Ovipositing females of Nupserha bicolor Thoms, ssp. postbrunnea Breun. cause loss of stem length in jute, Corchorus olitorius, by girdling the stem above and below a slit in which the egg is laid. The slit is made by two successive indentations of the mandibles. It is composed of a central pit and two lateral punctures. Girdling is restricted to that portion of the stem which falls within the stem-diameter range of 0·2 cm. to 0·4 cm.A relationship exists between the length of the mandibles of the female, the depth of the stem tissue from the epidermis down to the periphery of the pith (extra-medullary tissue), and girdling and oviposition.For girdling, the optimum ratio between the mandibular length and the depth of extra-medullary tissue as measured from the epidermal furrow and ridge of the stem (pentagonal in this region) is 1:0·80 and 1:0·99, respectively. Frequency of girdling gradually decreases in those regions of stem where the depth of extra-medullary tissue increases or decreases these ratios.
The Mosquitos of south Thailand
Authors: Iyengar M. O. T. , Menon M. A. U. 
Published: July 2009

The present list of the mosquitos of south Thailand makes certain corrections to a list previously published and adds Anopheles barbumbrosus Strickl. & Chowd. and Anopheles letifer Sandosham to the list.Taxonomic notes are given on eight species and a description of the larva of Uranotaenia bimaculiala Leic., previously undescribed, is included. The characters by which U. bimaculiala can be separated from the closely allied U. micans Leic. and U. edwardsi Barraud are detailed.
Effect of Post-treatment Temperature on Insect Resistance to Insecticidal Sprays
Authors: Pradhan S. , Rangarao P. V. 
Published: July 2009

SummaryResults are given of investigations on the effects of five post-treatment temperatures on the mortality of adults of Tribolium castaneum (Hbst.) sprayed with five or six concentrations of each of six insecticidal formulations, emulsified solutions of DDT, γ BHC, toxaphene, chlordane and parathion and a suspension of DDT.With both emulsified solutions and suspensions of DDT and emulsified solutions of γ BHC the mortality of the insects decreased with the rise of temperature from about 14° to 30°C. and increased when the temperature increased from 30° and 40°C. On the other hand, with emulsified solutions of toxaphene, chlordane and parathion, the mortality of the test insects increased continuously with increase of temperature from 14° to 40°C. As a possible explanation for such divergent results with different insecticides it is tentatively suggested that whilst the inherent physiological resistance of Tribolium to DDT and γ BHC formulations which appear to increase with increase of temperature up to a certain point has been demonstrated, the technique has not been sufficiently critical in the case of the other formulations, and it is thought that physiological resistance has possibly remained masked by other factors and that the values of LC50 are not a true index of physiological resistance in the ease of these insecticides.An essential similarity between the curve obtained by plotting values of LC50 against temperature in the case of DDT and γ BHC and those relating temperature to other physiological activities (published by various workers) has been stressed, implying a similarity between the resistance of the insect to insecticides on the one hand and its other physiological activities on the other.
Studies on the Choice of Food-plant and certain Aspects of the Digestive Physiology of the Larvae and Adults ofAthalia lugens proxima(Klug) andEpilachna vigintioctopunctata(F.)
Authors: Srivastava P. D. 
Published: July 2009

SummaryAthalia lugenssubsp.proximo(Klug) is a pest of cruciferous crops, and shows special preference for turnip. In the matter of selection of food, smell and taste of the food and the age of the plant are important factors.Epilachna vigintioctopunctata(F.) is a pest of solanaceous plants, particularly brinjal. In this insect only smell and taste are important factors in the selection of food.The hydrogen-ion concentrations of the salivary gland, foregut, midgut and hindgut of the larva ofAthaliaare 6·4–6·6, 6·4–6·8, 6·6–6·8 and 7·0 and of the adults 6·2–6·4, 6·4–6·6, 6·4–6·6 and 6·6, respectively. The hydrogen-ion concentration of the salivary gland, foregut, midgut and hindgut of the larvae ofEpilachnaare 5·4, 6·4–6·8, 6·0 and 6·0 and of the adult 6·6–6·8, 6·2, 6·0 and 5·4–5·7, respectively.The foregut and hindgut of the larvae and adults ofAthaliaandEpilachnado not secrete enzymes; the salivary glands of both larva and adult ofAthaliasecrete amylase, the midgut epithelium of both larva and adult ofAthaliasecretes amylase, maltase, invertase, lactase, lipase and protease. The salivary glands of the larva ofEpilachnasecrete amylase, but those of the adult do not, and the midgut epithelium of both larva and adult secretes amylase, maltase, invertase, lactase and protease. The midgut of both larva and adult ofEpilachnasecretes lipase also, although in the adult no more than traces are detectable. The proteases in both insects act in slightly acidic media.
Effect of Host-plant on the Resistance of Acyrthosiphon pisum (Harris) to Insecticides
Authors: Potter C. , Gillham E. M. 
Published: July 2009

SummaryBy means of a laboratory spraying technique, ten comparisons were made of the resistance to rotenone of samples of adult apterous viviparous parthenogenetic females of the Pea Aphid, Acyrthosiphon pisum (Harris), reared on broad bean and on clover, respectively. In nine of the tests, the Aphids from clover were more resistant than those from broad bean, the ratios ranging from 1·1 to 2·5. These differences were not all significant. In the remaining test the Aphids. from broan bean showed a very small increase in resistance over the Aphids from clover which was not significant.The Aphids from the clover were generally smaller than those from broad bean. Figures are given to show that while the total amount of poison retained by the larger individuals from broad bean was more than that retained by the smaller individuals from clover, the amount of poison retained per unit body weight was greater with the smaller individuals. It appears, therefore, that while the results obtained might be due, at least partially, to the greater total weight of poison retained by the larger individuals from broad bean, the difference in resistance between the insects from broad bean and clover, respectively, might be even greater if the poison were applied on the basis of equal weight of poison per unit of body weight. Since the difference in resistance between the Aphids from the two host-plants did not appear to depend primarily on difference in size, the assumption might be made that it is due to difference in nutrition. It was found that Aphids reared on clover had a significantly higher proportion of dry matter in their composition than those reared on broad bean, which may be taken as evidence that differences due to nutrition are being produced. These may lead to differences in resistance.
Insecticide Studies on East African Agricultural Pests. I.—Epilachna hirta (Thnb.). II.—Cylas puncticollis Boh
Authors: Walker P. T. 
Published: July 2009

SummaryResults are given of laboratory trials of insecticides, carried out in Kenya, against two pests of agricultural crops in East Africa. Against Epilachna hirta (Thnb.) (Col., COCCINELLIDAE), the adults and larvae of which feed on the foliage of wheat and other crops, dusts containing 0·5 or 2 per cent, parathion, applied at rates to give 0·74 to 2·97 mg. active ingredient per sq. ft., were the most rapidly effective against the adults. A 5 per cent. DDT dust, at rates giving 0·36 to 5·82 mg. technical DDT per sq. ft., was less rapid in action but produced very good results by the end of three days. A proprietary BHC dust, used at rates giving deposits of from 0·23 to 1·04 mg. γ isomer per sq. ft., was less effective and, at the highest rate used, only reached 100 per cent, mortality after eight days.Several insecticides were tested in emulsified solutions against Cylas puncticollis Boh. (Col., CURCULIONIDAE), one of the important sweet-potato weevils of East Africa. All the insecticides were applied at concentrations of 0·02, 0·1 and 0·5 per cent, active ingredient, and at a deposit rate of 0·813 mg. of spray per sq. cm. DDT was the most effective after 18 hours, but γ BHC was only slightly inferior.