bluuebunny/crossref_metadata_2025_split huggingface dataset:
New Species and Records of Diatraea Guilding and Zeadiatraea Box from Mexico, Central and South America (Lepid., Pyral.)
Authors: Box Harold E. 
Published: July 2009

Records are given of the localities (with altitudes) of approximately 900 specimens representing 21 species of Diatraea Guild, and four species of Zeadiatraea Box, from Mexico, Central and South America. Most of the moths were reared from known food-plants (all Gramineae) and the larvae of several of them are important agricultural pests as stalk-borers in sugar-cane and maize.Three species of Diatraea are described as new to science and their genitalia are figured, viz., colombiana, sp.n. (Colombia), balboana, sp.n. (Panama) and veracruzana, sp.n. (Mexico). The previously unknown male of D. instructella Dyar (Mexico) is described and its genitalia figured. These moths (except colombiana) are illustrated in the Plate. An attempt is made to clarify the confusion which has existed concerning D. magnifactella Dyar and the closely related D. considerata Heinrich, both of which are endemic in Mexico, but each with its own area of distribution without overlapping. The paper includes additional records and observations on the polytypic D. busckella Dyar & Heinrich and certain of its subspecies in Panama and Venezuela, previously discussed by the writer in this journal in 1951.
Experiments with a Systemic Insecticide for the Control of Schoenobius incertulas (Wlk.) (Lepidoptera, Pyralidae), A Stem Borer of Paddy in West Bengal
Authors: Banerjee S. N. , Basu A. C. 
Published: July 2009

SummaryExperiments were carried out in West Bengal to ascertain whether the Paddy Stem Borer, Schoenobius incertulas (Wlk.) could be controlled by “Tetrax” 1, a systemic insecticide containing technical schradan equivalent to approximately 42 per cent, octamethyl pyrophosphoramide + approximately 25 per cent, triphosphoric acid pentadimethylamide.In a preliminary experiment, treatment had little effect on the damage caused by the borer but the yield of grain was higher from a treated plot than from a control plot.A further experiment was carried out, the following year, in which the seed was soaked in a 0·1 per cent, water solution of “Tetrax” 1 for eight hours before sowing in the seed beds. The seedlings were lifted about 2½ months later and steeped in 0·1 per cent. “Tetrax” 1 for eight hours before transplanting into two plots, each 32 ft. × 32 ft. About three weeks later the plants were sprayed with a solution of the same strength. Two plots of similar size, in which the paddy had received no treatment, were maintained as controls.Again there was very little difference, between the treated and untreated plots, in the damage caused to the ear heads by the pest, but the treated plots produced 108·68 lb. of grain as against 77·27 lb. for the untreated plots. The increase was largely due to an increase in the number of ear heads per plant.The incidence of the borer was too low in both experiments to determine whether “Tetrax” 1 exercised any appreciable control, but the treatment did give rise to a higher yield of grain under the conditions of the experiments.
The Periodicity of Aphid Flight in East Africa
Authors: Eastop V. F. 
Published: July 2009

SummaryContinuous trapping of winged Aphids was carried out with Moericke trays and a suction trap for two years at a site at 6,850 ft. above sea level in Kenya, and with Moericke trays, for four months only, at a site at 1,200 ft. in southern Tanganyika.The trap data show a marked seasonal periodicity of flight (three-quarters of the annual catch in two months) at the Kenya site. The large catch is a reflection of a large increase in population following the rains. A similar relation between size of catch and the period of the rains is indicated by the data from Tanganyika.Successive hourly catches with a suction trap show no distinct diurnal double peak of aerial density such as occurs in Europe.
The Effects of a chemical Defoliant on an isolated Tsetse Fly Community and its Vegetation
Authors: Fryer J. D. , Johns D. L. , Yeo D. 
Published: July 2009

SummaryThree aerial applications of the n-butyl ester of 2,4,5-trichlorophenoxyacetic m acid (2,4,5-T) in diesel oil were made at intervals of six weeks to an isolated woodland community on a peninsula in Lake Victoria, Kenya. The woodland contained two species of tsetse fly, Glossina pallidipes Aust. and G. palpalis (R.-D.) (subsp. fuscipes Newst.). The object of the treatment was to defoliate the woodland in order to ascertain whether the reduction in shade would control the tsetse fly. It was also desired to obtain further information on the effect of the spray applications on the woody plant species.The first application, at an estimated actual dosage of 2·2 lb. 2,4,5·T per acre, resulted in a rapid defoliation of 13 out of the 15 observed leafy species, eight of, which subsequently died during the following nine months. Two succulent species of Euphorbia also died during this period. Of the remaining two species, one was fully defoliated only after the third application but recovered slowly, while the other, Lecaniodiscus vaughaniae, was but slightly affected at any time.No significant reduction in the numbers of tsetse fly was observed during the nine-month period following the first spraying. The following factors probably account for this lack of effect: the varying rate of defoliation of the different plant species, the resistance to the spray of one locally abundant species, the persistent shade cast by the stems of the thick vegetation after defoliation and the relatively humid climate during the period of maximum defoliation. These factors allowed an environment favourable for the tsetse fly to exist in one part or another of the peninsula in spite of the severe effects on the vegetation.Nine months after the first spraying, between a third and a half of the vegetation was destroyed during the dry season by an accidental fire. The effect on G. pallidipes was almost immediate, and two months later the population had been reduced to a fairly low level, which was maintained for the last 16 months of the experiment. The fire hardly affected the environment of G. palpalis and the main effect of defoliation was to cause this species to concentrate near the shady lake shore, where the dominant tree was Lecaniodiscus vaughaniae.There is little doubt that the destruction of the vegetation by fire was made possible by the effects of the spray applications, as the hitherto evergreen thicket would normally have been unburnable. While this suggests a possible new technique for bush clearance, further trials have indicated several factors which may make difficult a satisfactory burn following defoliation.Details are given of the assessment of the spray droplet performance both in calibration trials and during the applications to the peninsula.
Comparative studies on sibling species of the Anopheles gambiae Giles complex (Dipt., Culicidae): bionomics and vectorial activity of species A and species B at Segera, Tanzania
Authors: White G. B. , Magayuka S. A. , Boreham P. F. L. 
Published: July 2009

Collections of Anopheles gambiae Giles complex, A. funestus Giles group and other mosquitoes were made by spray-catch from twelve catching stations indoors and by hand-catch from pit shelters at two catching stations at Segera, Tanzania, between January 1970 and June 1971. Females of A. gambiae were identified cytotaxonomically as sibling species A or B of the complex. In houses during 1970, A. gambiae species B was more numerous at first than A, but A became predominant during the long rains of March-May. In the cool dry weather of June-November both A and B densities declined and the A:B ratio surpassed 50:1. The short rains in December produced a population explosion of species B and less multiplication of species A, the B:A ratio reaching >11:1. In 1971, hot dry weather during January-March caused declines of species A and B with a maximum B: A ratio of 13:1. Long rains, coming in late March, provoked a resurgence of A and a concurrent decline of B, so that the A:B ratio again reached 20:1 in June. Similar cycles of species A and B were observed outdoors, although the relative numbers outdoors/indoors averaged 2·3 times more for species B than for species A. In A. funestus, A. gambiae species A and A. gambiae species B Human Blood Indices were 97·5%, 91·2% and 60·9% indoors and 24%, 2% and 7% outdoors, respectively. Respective malaria sporozoite rates were 1·62%, 4·23% and 0·32% and minimum rates of stage-Ill filarial infection were 0·33%, 0·44% and 0·57%. Sporozoite-positive and sporozoite-negative mosquitoes exhibited similar HBF's in species A and discrepant HBI's in species B. The HBI's were higher in filariapositive A and B females than in filaria-negative females. Gregarines occurred in 1·36% of species A and 0·38% of species B. Trematode cysts were seen in two specimens of species A.Of A and B females 28% and 4%, respectively, had four-banded palps. It is shown mathematically that the discrepant malaria sporozoite rates in species A and B may be explained by extrapolating from the man-biting rate and probable daily survival rate for each species. This implies that no unrecognised factors play a major role in causing the contrasting efficiency of these two sibling species as malaria vectors.
The collection of spray droplets by flying locusts
Authors: MacCuaig R. D. 
Published: July 2009

An account is given of work carried out since that of Wootten & Sawyer (1954) on the pick-up of spray droplets by flying locusts. The same species,Schistocerca gregaria(Forsk.), was used. The values given in their work for the amounts of spray collected were confirmed, but when observations were extended to cover smaller droplets (less than 50-μ. diameter), locusts were found to collect these much less efficiently.Other factors affecting pick-up were sex (females collected more spray than males) and flying speed (faster-flying locusts tended to collect less spray per unit of distance flown). When the angle of approach of the droplets to the flying locusts was varied between 1 and 11° from the horizontal no difference in the pick-up of spray could be detected.For droplets between 60- and 300-μ diameter, the dose of insecticide collected by the locusts is given by the formula 9xPC μg. for males, and 11·5xPC for females, when the locusts fly through a concentration of spray ofCml. per cu. m. for a distancePm. and the spray solution containsxper cent, (w/v) of insecticide.
Dispersal of alates and establishment of new colonies in Cryptotermes havilandi (Sjöstedt) (Isoptera, Kalotermitidae)
Authors: Wilkinson W. 
Published: July 2009

Cryptotermes havilandi (Sjöst.) is an important pest of domestic timber in West Africa, and in 1957 a study of certain aspects of its biology was made at Port Harcourt, Nigeria.The alate is positively phototactic on emergence, and the main flights occur at dusk, between 1800 and 1900 hr. Heavy flights continue until 2200 hr., but few alates can be seen after 0100 or before 1600 hr. There is a peak of activity in the drier months of January and February, but flights take place in every month. Emergence for flight is associated with drier atmospheric conditions.After a change to negative phototaxis, followed by shedding of the wings, the dealates search for a nest site. Tandem behaviour does not occur. The dealates cannot bore into sound wood, and a hole or crack is essential for colony foundation. The entrance to the hole is sealed with material carried in the gut of the insect, according to a fixed behaviour pattern. Dealates seeking to enter wood prefer holes between one and a half and three millimetres in diameter, and cannot use those of less than one or more than five millimetres in diameter. Preference by dealates for particular species of wood was not shown conclusively. There was no discrimination against wood containing lethal doses of borax or Celcure (a proprietary mixture consisting essentially of potassium dichromate, copper sulphate and acetic acid or chromium acetate).The rate of egg-production, the incubation period, and the duration of the first three instars are recorded. At the rate estimated, egg-production by a physogastric queen could maintain populations in excess of 3,000. Neoteinics are readily produced in isolation from all but the first three larval instars. They may lay eggs from 35 days onwards, and in their first year have much greater fecundity than primary queens.The economic applications of the observations and experiments are discussed, together with some factors affecting testing of timbers against termite attack.
A diurnal and seasonal study of the resting behaviour ofGlossina pallidipesAust.
Authors: Pilson R. D. , Leggate B. M. 
Published: July 2009

In conjunction with an investigation of the diurnal and seasonal feeding behaviour ofGlossina pallidipesAust. in dense riverine vegetation in the Zambezi Valley, Southern Rhodesia, gorged flies caught on a stationary ox were marked and released and their subsequent resting places recorded. Fallen logs, a rot hole, boles and branches were found to be utilised in the late hot dry season (November), but in the rainy season (February), the cool season (May) and the early dry season (August), flies were found almost entirely on branches. Of the total resting flies observed, 89 per cent, were at heights of 0 to 9 ft., but whereas in November 49 per cent, of resting flies were at heights between 0 and 3 ft., only 10 to 19 per cent, rested at this level in the other seasons. The choice of more deeply shaded resting sites in November is thought to be due to a reversal, at temperatures over 35°C., of a normally positive reaction to light. The resting behaviour did not appear to differ greatly between sexes, although females do not move so readily as do males on to sites other than branches.In November, a diurnal pattern of resting behaviour was noted. A branch type of site was preferred in the early morning, but a shift to the rot hole and boles was evident during the middle of the day, followed by a return to branches in the evening; there was evidence that flies rested in yet another type of site at night. In May, searches from 1930 to 2100 hr. for flies marked with reflecting paint revealed some on leaves and small twigs.
Control of ground beetles (Col., Carabidae) attacking strawberry fruits
Authors: Briggs J. B. , Tew R. P. 
Published: July 2009

Experiments in south-east England are described in which insecticides were tested against the Carabid beetles Harpahis rufipcs (Deg.) and Feronia melanaria(111.), which cause damage to strawberry fruits.In preliminary screening tests, the mortality of H. rufipex was low when adults were caged with fruits or straw treated with rotenone at 0·004 per cent, or with carbaryl, DDT, dimethoate, malathion, mevinphos, nicotine, TEPP, toxaphene and trichlorphon at one or more concentrations in the range 0–06–0–2 per cent. In small-scale field trials, γ BHC at 0·026 per cent, gave poor results but chlordane and dieldrin exhibited persistent toxicity.In further tests with fruits, field-weathered deposits from sprays containing 0·1 or 0·2 per cent, dieldrin caused over 90 per cent, mortality for 7 and 21 days, respectively, but left residues at harvest of 0·5 p.p.m., which were considered too high for consumer safety.Dieldrin applied to soil at 5 lb. per acre resulted in 100 per cent, mortality for 28 days in 1957, but gave very variable results in 1958. Conversely, aldrin at 5 lb. gave effective mortality for only 14 days in 1957 but for the maximum test period of 89 days in 1958; no satisfactory explanation was found for the seasonal differences. Aldrin at 10 lb. per acre gave 100 per cent, mortality for 77 and 89 days, respectively, in the two years. Tests of soils into which measured quantities of insecticide had been incorporated, resulted in 100 per cent, mortality, after 4 days' exposure, with aldrin and dieldrin at levels of 2–4 and 16–32 p.p.m., respectively; endrin at 64 p.p.m. was only slightly toxic.In field trials in 1959–60, application of aldrin at 10 lb. per acre to the surface of the soil around the plants in sprays in late April immediately before flowering, or at 5 lb. per acre in late May before laying straw below the fruit, reduced fruit damage due to H. rufipes or F. melanaria by 66–94 per cent. Residues at harvest were of the order of 0·03 p.p.m., and no effect on flavour was detected in processed fruit from plots treated at either time of application.
A key to the larvae of some species of Phycitinae (Lepidoptera, Pyralidae) associated with stored products, and of some related species
Authors: Aitken Audrey D. 
Published: July 2009

A key to the fully grown larvae of 11 species of Phycitinae is given. Of these, the following eight are known in Britain either as stored-products pests or associated with imported food:—Ephestia elutella(Hb.),Anagasta kuehniella(Zell.),Cadra cautella(Wlk.),C. calidella(Gn.),C. figulilella(Gregson),Plodia interpunctella(Hb.),Mussidia nigrivenellaRag. andEctomyelois ceratoniae(Zell.). The key is preceded by a brief account of the economic importance of these species in Britain.The other three species areEctomyelois decolor(Zell.),E. muriscis(Dyar) andParamyelois transitella(Wlk.). Although these are native to the Americas and are unknown in Britain, they comprise, together withE. ceratoniae, the economically important species formerly of the genusMyeloisHuebner.The larvae ofMussidia nigrivenella, P. transitellaand of the three species ofEctomyeloisare described.
The influence of environmental conditions on the contact toxicity of some insecticide deposits to adult mosquitos, Anopheles stephensi List
Authors: Hadaway A. B. , Barlow F. 
Published: July 2009

Investigations have been made on the influence of environmental conditions on the contact toxicity to adult mosquitos (Anopheles stephensi List.) of two kinds of insecticidal deposits of importance in sprayed houses, superficial deposits from wettable powders and insecticides sorbed on dried soils.Increasing the relative humidity from 43 to 80 per cent, during the contact period had no effect on the toxicity of wettable-powder deposits on plywood of dieldrin, Sevin and O-methyl O-(2,4,5-trichlorophenyl) ethylphosphoramidothioate. On the other hand, the availability of DDT, dieldrin and 3-isopropylphenyl N-methylearbamate sorbed on dried soils increased considerably as atmospheric humidity increased. The logarithm of the median lethal exposure time was linearly related to atmospheric humidity, and decreased by a factor of 2·8, 2·2 and 2·1 for the carbamate, dieldrin and DDT, respectively, for each 10 per cent, increase in relative humidity. There was also a linear relationship between the logarithm of the water uptake of a given soil and humidity.Temperature affected the action of insecticides during both the contact period and the post-treatment period. Median lethal doses of dieldrin, Sevin and the phosphoramidothioate decreased, and that of DDT increased, as the post-treatment temperature increased from 20 to 30°C. These effects of the post-treatment temperature were also found when treatment was by exposure to residues. When these effects were eliminated it was found that the contact toxicity of superficial deposits on plywood and of insecticides sorbed on dried soils increased as the temperature during the exposure period increased. A simple relationship between median lethal time and exposure temperature was indicated.
Preliminary studies on the biology of Orasema assectator Kerrich (Hym., Eucharitidae), parasitic on Pheidole and causing damage to leaves of tea in Assam
Authors: Das G. M. 
Published: July 2009

The so-called ‘sewing blight ’ of tea in Assam is an effect of oviposition in the young leaves by two species of Eucharitid, Orasema initiator Kerrich and O. assectator Kerrich. The affected leaves develop brown spots round the oviposition punctures, wither prematurely and adversely affect the quality of the made tea. Normally only a small proportion of bushes is affected and these are associated with the presence of nests of an undetermined species of Pheidole.An account is given of the life-history of O. assectator, and the developmental stages are briefly described. The eggs are laid singly in incisions made by the ovipositor on the underside of the leaf in parallel rows arranged lengthwise. The newly hatched larvae exist as free-living planidia on the leaf surface, whence they are carried by unknown means into the ants' nests in the soil beneath the tea bushes. Here the planidium transfers to the last-instar larva of the ant and penetrates its body. There it remains inactive until its host reaches the prepupal stage, whereupon endoparasitic feeding and development start. After the host pupa has formed, the parasite larva emerges, establishes itself below the thorax of its host, and remains there, feeding ectoparasitically, through two further instars, completely consuming the contents of its host. The mature larvae remain scattered in the ant's nest and pupate a few days later; both larvae and pupae are cared for by the worker ants.
An evaluation by bioassay of the persistence of DDT deposits on riverine vegetation in the Northern Guinea Savannah vegetation Zone of Nigeria and observations on the factors influencing the availability of deposits to Glossina palpalis (R.-D.)
Authors: Baldry D. A. T. 
Published: July 2009

The persistence of DDT deposits, derived from dilutions of an emulsion concentrate, Arkotine D.25, on the leaves of riverine vegetation in the Northern Guinea Savannah vegetation zone of Nigeria was studied in the laboratory by a bioassay method using teneral females of Glossina palpalis (R.-D.) as test insects. Irrespective of whether sprayed in the dry or wet season, deposits derived from sprays containing 5.0 per cent. DDT produced by the Warley knapsack sprayer were still reasonably toxic one year after spraying. Deposits derived from sprays having a concentration of DDT varying from 1·25 to 5·0 per cent. DDT were equally toxic when young, but those from the lower concentrations were weathered much more rapidly than those from the 5·0 per cent, sprays. Young deposits produced by Warley and Motoblo sprayers were equally toxic, but deposits from the Motoblo deteriorated more rapidly than those of the Warley.The toxicity of the DDT deposits on leaves varied regularly with the seasons. The various climatic factors that it is thought influenced the variations in toxicity are discussed. Accumulations of wind-blown dust on the leaves during the late dry season and low evaporation rates at the height of the rains appear to be responsible for reduced toxicity at those times; in the early wet season, the occasional violent storm probably washes off the leaves the dust accumulated during the dry season and makes the insecticidal deposits once more available. Heavy rainfall is important in removing the insecticidal deposits from the vegetation, and leaf decay and refoliation are important in reducing the availability of the deposits. The implications of these variations in toxicity and factors that reduce the availability of the deposits are discussed in relation to the eradication of riverine tsetse.Great differences in the rates of foliage decay and refoliation occur between different riverine plants, and it is suggested that a thorough study of this feature in riverine plants and of resting sites favoured by tsetse flies might reveal information that would enable tsetse to be eradicated by selective spraying of certain plant species only.