bluuebunny/crossref_metadata_2025 huggingface dataset:
The forms of Syntomosphyrum (Hym., Eulophidae) parasitic on tsetse flies
Authors: Kerrich G. J.
Published: July 2009

The object of this paper is to give taxonomic consideration and status to the ‘white-clubbed’ parasite of tsetse flies that was studied by Dr. D. S. Saunders in the foregoing paper. Since the biological evidence in conjunction with the distribution suggests that it is specifically distinct from Syntomosphyrum glossinae Waterston it is described as a new species, although the morphological separation is weak.
The effect of humidity and temperature on the extent of abdominal pigmentation inGlossina pallidipesAusten
Authors: Bursell E.
Published: July 2009

The extent of pigmentation of the abdominal bands ofGlossina pallidipesAust. was studied in specimens emerging in the laboratory from puparia maintained at constant temperature and a range of relative humidities and derived from females collected in the field at Shinyanga, Tanganyika. An index of pigmentation was obtained by regarding the bands as consisting in all of 15 zones, each carrying a score of 1.

The index was closely dependent on the humidity experienced during pupal development, almost full pigmentation being produced in saturated air and almost complete suppression of it in dry air; it is inversely related to size and little affected in nearly saturated air by temperatures below 28°C. during pupal development, although still higher temperatures reduce it quite sharply.

In flies collected in the field throughout the year, most of those taken towards the end of the rains (March and April) fell into the darker pigment categories; as the dry season advanced the distribution tended to become bimodal, with the darker mode relatively steady at an index of about 12 and the paler mode moving progressively down the scale, reaching an index of about 5 in October and then disappearing. December and January collections (rainy season) were again unimodal, resembling those of March. It is suggested that these changes reflect the use of two types of larviposition site, the darker mode representing pupae from the evergreen thickets along the drainage lines and the lighter mode those from semi-deciduous thickets on the eluvial slopes, and that during the dry season the soil-space humidity in the latter sites may reach levels inimical to survival.

The depth to which larvae ofG. pallidipesburrow appears to be related to the temperature, and perhaps the humidity, obtaining at the time of larviposition.

The possible effect of humidity on coloration was tested in four other species of tsetse fly, namelyG. swynnertoniAust.,G. morsitansWestw.,G. palpalis fuscipesNewst. andG. longipennisCorti. OnlyG. swynnertonigave indications of some slight effect.
Further observations on lake-side and riverine communities of Glossina palpalis fuscipes Newstead
Authors: Bursell E. , Glasgow J. P.
Published: July 2009

Earlier work in Nyanza Province, Kenya, had led to the conclusion that riverine communities of Glossina palpalis fuscipes Newst. were permanently hungrier than lake-side communities. This was based on analysis of catches (percentage of teneral flies in the whole catch, and percentage of females among non-teneral flies) and on a behaviour criterion (percentage of non-teneral males caught on the party), but subsequent observations in the two types of habitat, in which a different area was used to represent the lake side, showed the lake-side flies to be slightly smaller than the riverine flies and not to differ in fat content, and a further investigation was accordingly made.

Puparia were collected on three dates between January and March 1958 and their surface area measured. A measure of the thoracic surface and fat content was taken of all adults emerging. Non-teneral flies were collected, for comparison, about two weeks later than the puparia.

In all samples, the riverine puparia were significantly larger than those from the lake side, and flies that emerged showed a comparable difference in size, but not in fat content corrected for size. Non-teneral riverine flies were slightly larger than lake-side ones but the difference was less than half that shown by the puparia and the teneral flies obtained from them. Evidence is adduced to show that this discrepancy is due to elimination of the lower size-groups in the lake-side community. Estimates of fat content of non-teneral flies support the conclusion that the lake-side community was under stress as compared with the riverine one, and analysis of available fly-round data from the lake side also suggests stress conditions.

The lake-side results are at variance with those from the site used in the earlier work. Available meteorological data show that the average temperature during February and March is 2°C. higher at the present site than at the former; such difference may directly cause the stresses that appear to be operating in the present instance.

The results suggest that the percentage of non-teneral males caught on the party has a real meaning in terms of nutritional status, and that it is also a very responsive indicator, but that the proportions of tenerals and of female nontenerals may not be simply related to the nutritional state as had hitherto been supposed.
The effects of different plant foods on the fecundity, fertility and development of a cotton stainer,Dysdercus superstitiosus(F.)
Authors: Geering Q. A. , Coaker T. H.
Published: July 2009

Dysdercus superstitiosus(F.) is capable of utilising a much wider range of food-plants than was previously supposed, and is able to complete a full breeding cycle on the several diets other than cotton. This has been demonstrated by rearing and breeding adults and nymphs in the laboratory, in Uganda, on selected food material,e.g., Sorghum vulgare, Pennisetum typhoides, Zea maysandVigna unguiculata, immature seeds of each being used. Diets other than mature cotton seeds are less suitable for breeding, as judged by fecundity of females and development of nymphs, but the influence of nymphal diet on adult fecundity is not consistent. Females reared on sorghum are smaller than those reared on cotton seed and they may lay fewer eggs.

There is an indication that varieties of sorghum may differ in their suitability for producing maximum fecundity and fertility. Those varieties to which the stainer exhibits a predisposition in the field may not be the most suitable.

When adults are fed on cotton bolls of ages 1–10 weeks, the fecundity of females, and the rate of egg-production increase with increasing age of boll, and the preoviposition period decreases.

Stored cotton seed may be less suitable for egg-production than freshly harvested seed cotton.

Extraction of oil from cotton seed with petroleum ether does not wholly impair the fecundity rate of females fed on the seed, but may reduce the fertility and nymphal survival in the first instar.

A diet of cotton seed, heat treated at 150–190°C. for one hour, reduces the fecundity in the females, possibly by destroying the accessary food factors. Nymphal survival is possible on such treated seed, but not when thus heated for two hours at or above 150°C.
The swamp-breeding mosquitos of Uganda: records of larvae and their habitats
Authors: Goma L. K. H.
Published: July 2009

Some 246 species of mosquitos are known to occur in Uganda. Of these, 92 (37·4%) have been recorded as breeding in swamps, and the present paper brings together published data and the results of work on the collection and identification of larvae from habitats in a wide variety of types of swamp between 1955 and 1958. Notes on the occurrence and habitats of the larvae are given under each species.

In the present work, only 58 species were found breeding, but these included six new swamp records. Only 26 species appear to breed exclusively in swamps. In addition to the species identified, larvae representing some 14 unrecognised and probably undescribed species were collected. The majority of the swampbreeding species are Culicines, the Anophelines comprising only 21·7 per cent.

The swamp environment in Uganda, with respect to the breeding of mosquitos, is extremely varied. Some possible classifications of the many and various swamps found in the country are given. The distribution of certain species of mosquitos is more or less limited to certain types of swamp This is briefly discussed and examples are given. There is also a definite zonal distribution of some species within a swamp,e.g., Culex (Culex) grahamiTheo.,C. (C.) guiartiBlanch, andFicalbia (Ficalbia) malfeytiNewst. occur only in peripheral zones. In general, the interior of the large swamps is unfavourable to the breeding of Anophelines, but Culicines are very abundant there.

Breeding of mosquitos is profoundly affected when swamps are altered by human interference. In certain cases this has resulted in increased production of Anophelines, with the consequent aggravation of the malaria situation.

It is concluded that, from the point of view of human disease, the swamps of Uganda (especially in their natural untouched state) are not as dangerous as previously thought.
Pentalitomastix, a new name for Pseudolitomastix Eady (Hymenoptera, Chalcidoidea).
Authors: Eady R. D.
Published: July 2009

The name Pseudolitomastix was applied (Eady, 1960) to a genus erected for the new species P. nacoleiae, bred from Nacoleia octasema (Meyr.). This unfortunately overlooked the valid and prior use of the name Pseudolitomastix, by Risbec (1954). The two species for which Pseudolitomastix Risbec was erected are generically quite distinct from P. nacoleiae, so that a new generic name is required for this latter species. The name Pentalitomastix, indicative of the five-segmented funicle of the female antenna, is hereby proposed. I am grateful to Dr. O. Peck, of the Entomology Research Institute of the Canadian Department of Agriculture, for drawing my attention to the homonymy, and to my colleague Mr. G. J. Kerrich for suggesting the new name.
Occurrence of the red spider, Oligonychus coffeae (Nietner), on tea in north-east India in relation to pruning and defoliation.
Authors: Das G. M.
Published: July 2009

The red spider, Oligonychus coffeae (Niet.), persists in all stages of its development on a few old leaves and ‘ janams ’ (small leaves at the base of the shoot) of tea bushes during the cold weather, and this persisting population is primarily responsible for the attack in the spring.

In pruning, a great many of the old leaves (including janams) are removed from bushes, and, concomitantly, the red spider. Pruned tea is, therefore, less attacked than unpruned tea or ‘ skiffed ’ tea (where just a little is cut off the tops of the shoots) in which comparatively more leaves are left on bushes.
The biology of two species of mosquito,Mansonia africana(Theobald) andMansonia uniformis(Theobald), belonging to the subgenusMansonioides(Diptera, Culicidae).
Authors: Laurence B. R.
Published: July 2009

The distribution and biology of two related species of mosquito,Mansonia(Mansonioides)africana(Theo.) and M. (M.) uniformis (Theo.), have been compared.M. uniformisis found from China to Africa, whereas M. africana is restricted to the continent of Africa. The two species do not interbreed although mating, but no insemination, is possible in the laboratory. Strains ofM. uniformisfrom Africa, Ceylon and Malaya are interfertile, but crosses between the African and the other strains, especially, showed a reduction in fertility of the eggs produced and thus some evidence of speciation.

The two species show the same adult behaviour at mating, feeding (both in the field and in the laboratory) and during oviposition. Both species are stenogamous and mate readily in small cages. The first blood-meal is taken approximately 24 hours after emergence and immediately after each oviposition, 3–5 days after the previous blood-meal.M. uniformisis more active directly after the blood-meal.
The control of yellow tea mite, Hemitarsonemus latus (Banks), with DDT on cotton in Uganda.
Authors: Ingram W. R.
Published: July 2009

The damage caused to cotton by the yellow tea-mite,Hemitarsonemus latus(Banks),was first seen in Uganda in 1945 and is now known throughout the important cotton-growing areas of the country. Experiments on cotton in the Belgian Congo showed that sprays and dusts of several insecticides would control or prevent infestations of H.latus;earlier published work in Ugandasuggested that BHC reduced tea-mite damage and DDT increased it,when both were appliedas sprays from wettable powders.However,tea-mite damage was not noticeable on trials in which single rows of cotton were sprayed with DDT emulsion,or on large-scale trials using DDT formulated as a water-miscible liquid. These trials were all directed against the pest insects Earias spp. and Lygus vosseleri Popp.,the standard rate of application being 1 lb. active ingredientper acre applied four times at ten-day intervals.
The infestibility of stored paddy bySitophilus sasakii(Tak.) andRhyzopertha dominica(F.).
Authors: Breese Michael H.
Published: July 2009

Indications of the type of paddy grain most commonly infested bySitophilus sasakii(Tak.) andRhyzopertha dominica(F.) have been obtained from the examination of infested samples of paddy grown in Trinidad, W.I., and in British Guiana.

Small-scale experiments with sound mature paddy have shown that S.sasakii is unable to feed and breed in a grain with an intact husk, even when the moisture content is high. It is also probable that R.dominicafinds it extremely difficult to attack and infest such grains.

The rapid multiplication of S.sasakiiin paddy is dependent on there being a high proportion of grains with badly damaged husks. Infestation can occur in grains with a slight separation of the lemma and palea, or with slightly split husks, but the adult that develops is often unable to emerge from such grains.
Further Considerations regarding the repellency of spray components
Authors: Hocking B.
Published: July 2009

The apparatus previously used to demonstrate the repellent properties of DDT, fuel oil and methylated naphthalene auxiliary solvents towards certain Diptera was used in further studies of olfactory repellency in an attempt to narrow down the ingredients responsible for this effect, and consideration was given to the possibility of finding substitutes for them with less repellent or even attractive properties.

Light, medium and heavy fractions were obtained by fractional distillation of fuel oil and each of two methylated naphthalene auxiliary solvents. In all these spray components the repellent properties are inversely related to the boiling point, and appear to be non-specific both chemically and by insects. Tests with materials of low volatility, however, showed that the effect is not a simple broad relationship between volatility and repellency.

Butoxy-polypropylene glycol, widely used as a ‘repellent’ ingredient of livestock sprays, shows olfactory attractiveness to Musca domestica L. and Aëdes aegypti (L.). The odour of Drosophila melanogaster Mg. was shown to be attractive to the insect, regardless of sex.

It is concluded that there seems little hope of an economic non-repellent material.

It is suggested that the repellency of spray components might be counteracted by the addition of specific attractants, sex or other, to spray formulae. Alternatively, a useful space repellent spray, containing no toxicant, might be formulated from the lighter fractions of the solvent materials.
The development and oviposition of Oryzaephilus spp. on unrefined sugars
Authors: Breese Michael H.
Published: July 2009

Experiments were conducted with Trinidad strains of Oryzaephilus surinamensis (L.) and O. mercator (Fauv.), the average sizes of which were smaller than those given in the literature. Limited observations on their biology on cereal products showed that whereas the egg-production of O. mercator was comparable with that recorded by other workers under similar conditions, that of O. surinamensis was much lower.

Larvae of both species were able to complete their development on raw and yellow-crystal sugar, but there was a high mortality among those of O. surinamensis. Both species showed very low oviposition rates on sugar and this, together with a high larval mortality, would indicate that infestations of O. surinamensis on these products would die out. O. mercator, on the other hand, could multiply very slowly. Oviposition rates rise rapidly when females return from sugar to cereal products.

Unrefined sugars should accordingly not be disregarded as sources of Oryzaephilus infestation, especially in the humid tropics.
The attraction of mosquitos by human or animal baits in relation to the transmission of disease
Authors: Reid J. A.
Published: July 2009

Experiments were made at three different sites in Malaya between 1952 and 1957 to compare the numbers of mosquitos attracted to man, calf or goat under the same conditions. The baits being compared (either two men and one calf or two men and two goats) were exposed simultaneously in two net traps placed about 50 yd. apart. This procedure is referred to as comparative trapping.

The total number of mosquitos caught with each bait showed calf to be much the most attractive, followed by goats and then men. However, there were three species, the dark-winged form of Anopheles barbirostris Wulp, Aëdes albo-pictus (Skuse) and Culex pipiens fatigans Wied. that were attracted in larger numbers to man than to calf, and six species attracted in larger numbers to man than to goat.

To compare the host preferences of the different species as between man and calf, the numbers of each caught with man and with calf have been expressed as a ratio (the man: calf attraction ratio). For most species the ratios from the different sites were much the same, showing that the method produced repeatable results. The data from the three sites were therefore combined.

On the combined data the ratios range from 3·4:1 in favour of man for the dark-winged form of Anopheles barbirostris to 1:82 in favour of calf for A. vagus Dön.

As might be expected, the ratios show that the vectors of malaria, filariasis and virus diseases are among the more anthropophilous species.

Attraction ratios have been calculated from suitable data published by various authors for ten different species in five countries. The ratios obtained place the Anophelines in an order that agrees well with their status as vectors of malaria.

It appears that if the results of comparative trapping are expressed as attraction ratios, this offers a method of comparing the host preferences of mosquitos of the same or different species, at different times and places in a country, or even in different countries.
Observations on the effects of carotene on the growth and pigmentation of locusts
Authors: Dadd R. H.
Published: July 2009

A method of obtaining locust eggs which could be expected to be deficient in carotene is described. It involved rearing a parental generation on an artificial diet which, because of certain pigmentation abnormalities it induced, was probably itself deficient in carotene.

Using crowded hatchlings ofLocusta migratoria(L.) from eggs thus modified, it was shown that they were sensitive to dietary carotene, whereas hatchlings from normal eggs were indifferent. The absence of carotene was marked by inferior growth, lessened activity and most notably by an extremely different coloration in both hoppers and adults. Without carotene, melanisation was absent or greatly reduced and in many cases the integument developed a greenish-blue colour. With carotene, heavy melanisation occurred in the hoppers, and the colour of the adults was characteristically gregarious.

It was concluded that in normal eggs the amount of carotene present is usually sufficient to mask the expression of a dietary deficiency during nymphal growth, but that with normal eggs having low amounts of carotene, a dietary deficiency might become apparent as it did with modified eggs.

It is suggested that the blue colour of modifiedLocustahoppers reared without carotene is due to mesobiliverdin, a prochromogen of insectoverdin, the green pigment of thesolitariaphase of locusts. Insectoverdin itself could not be formed because it contains carotenoids, and these were absent from the diet. The effect of extreme deprivation of carotene is therefore to induce solitaroid tendencies, notably in regard to colour (suppression of melanin and production of mesobiliverdin) but also in regard to activity.

Crowded hoppers ofSchistocerca gregaria(Forsk.) reared on synthetic diets lacking carotene usually had turquoise-blue blood by the fifth instar. It was shown, by the electrophoresis of yellow, green and blue bloods in parallel, that the blue chromoprotein of blue blood is the same as the blue chromoprotein of green blood. Its prosthetic pigment must therefore be mesobiliverdin.

The abnormalities of coloration which arise in crowdedLocustaandSchistocercawhen deprived of carotene are normal in the solitary phase. Moreover, they resemble those abnormalities of coloration consequent upon the implantation of additional corpora allata into gregarious hoppers. The implications of this are discussed in relation to the validity of phase criteria, and an attempt is made to relate these findings to hypotheses on the humoral regulation of phase.
The development of Monoctonus paludum Marshall (Hym., Braconidae) in Nasonovia ribis-nigri on lettuce, and immunity reactions in other Lettuce Aphids
Authors: Griffiths D. C.
Published: July 2009

Aphids belonging to the species Nasonovia ribis-nigri (Mosley), Aulacorthum circumflexum (Buckt.), Macrosiphum euphorbiae (Thos.), Myzus persicae (Sulz.) and A. solani (Kalt.) were exposed to attack by the parasite, Monoctonus paludum Marshall, and were sectioned and dissected at various time-intervals after attack in order to observe the developmental processes of the parasite.

The egg was always laid in the posterior mass of fused ventral nerve ganglia in the thorax of the aphid host.

The development of the parasite in N. ribis-nigri, its normal host on lettuce, is described.

In the species A. circumflexum the development of the parasite was arrested after approximately 24 hours by the secretion around it of a thin brown capsule formed by certain of the host's blood cells.

In the other three species, Macrosiphum euphorbiae, Myzus persicae and A. solani, no capsule formation occurred. The development of the parasite embryos was rather variable in these but it was common for parasites in Macrosiphum euphorbiae to reach the stage normal for 24-hour embryos and for parasites in Myzus persicae and A. solani to reach stages rather less advanced than this before degenerative changes set in.

The degenerative changes in the parasite embryos are described for each species of aphid and the nature of these changes is discussed.
Studies of the sampling of Glossina pallidipes Aust. I.—The numbers caught daily on cattle, in Morris traps and on a fly-round
Authors: Smith I. M. , Rennison B. D.
Published: July 2009

Two experiments in which G. pallidipes Aust. was caught on oxen, in Morris traps and on a fly-round in south-eastern Uganda are described.

Fewer flies were caught in traps than on oxen, but the former took a higher proportion of females. The numbers in traps covered with natural-coloured hessian tended to be greater than in traps on which the hessian was painted black. A white ox attracted fewer flies than darker-coloured oxen, among which a red ox was the most attractive. Variations reflected in day and site effects indicated that the sexes were differentially affected by the factors controlling availability to the oxen and the traps. Fly-round data appeared to give an unsatisfactory estimate of the population density.

The numbers caught by the various methods were, in general, not correlated and this casts doubt on the validity of fly-round or trap data as estimates of the number of G. pallidipes likely to attack cattle.
Studies of the sampling ofGlossina pallidipesAust.—II. The daily pattern of flies caught on cattle, in Morris traps and on A fly-round
Authors: Smith I. M. , Rennison B. D.
Published: July 2009

A series of catches ofG. pallidipesAust. was made in 1½-hr. periods between 0800 and 1830 hr. each day during two experiments carried out in the early wet season (1957) and the late dry season (1958), at Lugala, Uganda, using tethered, small, shorthorned East African Zebu oxen, Morris traps and the standard flyround technique.

Flies were attracted to the oxen in greater numbers in the morning and evening than at midday, the evening increase being marked in the wet season. The daily catches of both sexes on oxen, though starting at much the same level in both seasons, fell to lower levels at the hotter times of day during the dry season and rose only slightly in the evening. Traps, on the other hand, in both seasons caught most females between 1230 and 1400 hr. and least in the mornings. Male flies were trapped in greatest numbers between 1400 and 1530 hr. in the wet season, but only in comparatively small numbers at any time in the dry season, though there was a suggestion of maximum availability between 1100 and 1230 hr. during the latter. During the dry season, catches on the fly-round and on oxen showed a similar periodicity in the case of females, but not in that of males, fly-round catches of which declined from a peak at 0930–1100 hr.
Problems in the Assessment of Tsetse Populations
Authors: Morris K. R. S.
Published: July 2009

A detailed tsetse-fly survey of 41,000 sq. miles in the inland savannah zone of the Gold Coast (Ghana) was completed in five years using an entirely African staff and working only six months each year.

This undertaking was made possible because studies of the species of Glossina concerned, G. palpalis (R.-D.), G. tachinoides Westw. and G. morsitans sub-morsitans Newst., had provided knowledge of their habitat, food-hosts and activity rhythm, on which could be based a standard yet simple survey technique, within the compass of independent native teams.

The restricted activity rhythm of the flies, subject to both daily and seasonal variations, meant that nothing less than a ‘day’ of eight hours of observation could be accepted as a valid sampling unit.

With tsetse flies at low densities, a day's search was inadequate, giving only 40 per cent, reliability compared with 6-day observations. Four days' search gave 90 per cent, reliability and was adopted as the minimum period of search.

Each survey team was under the charge of a Kecorder or Field Assistant, with fly-boys devoting the whole of their time to catching. Comparability of survey data was ensured by keeping teams to the same size, two fly-boys being the optimum, since it was found that the size of the catch was not always proportionate to the number of boys, the relationship varying according to a variety of factors.

In surveying G. palpalis and G. tachinoides the ‘picket’ system of more or less stationary teams, measuring their catches by the ‘day ’, was found overwhelmingly superior to the ‘fly-round’ technique.

The survey procedure described for savannah woodland country was not effective in sampling G. nigrofusca Newst. in the Ashanti forest or G. longipalpis Wied. in the coastal savannah, but Morris's ‘animal’ traps were found to take both species readily in places where they had not been detected or only occasionally caught by fly-boys. Experiments showed that trap catches were superior, both numerically and in giving a more representative sample of the tsetse population present. It was also shown that trapping could be a valuable means of studying the biology of these two ‘man-shy’ species of Glossina. Traps were also effective in taking G. pallicera Big. and G. medicorum Aust.

The greater value of traps compared with fly-boys as a means of sampling various species of tsetse fly is discussed, and suggestions are put forward for developing trapping as a method of survey.

The type of trap employed is regularly catching insects of several other families, including a number of species among the Tabanidae, and of several other orders.
The population dynamics ofCryptolestes ferrugineus(Stephens) (Col., Cucujidae) in flour and on Manitoba wheat
Authors: Ashby K. R.
Published: July 2009

If adults ofCryptolestes ferrugineus(Steph.), of which the females have already been fertilised, are cultured on flour at low densities, the rate of oviposition is independent of the density of adults and juvenile mortality is negligible. At high densities there is a heavy mortality amongst eggs and young larvae, and there is evidence that, providing no great degree of conditioning of the medium has occurred, an equilibrium is reached with the number of eggspluslarvae present at any time being independent of the density of adults. Cannibalism is undoubtedly a major cause of the juvenile mortality under these conditions. Where crowding of adults is so great that conditioning of the medium becomes important, the number of eggs plus larvae present at a given time after the cultures have been set up decreases with increasing density of adults, there being some indication of an inverse linear relation.

Cultures ofC. ferrugineuson a mixture at 70 per cent. R.H. of sound grain and grain already slightly damaged byCrypiolestesare capable of initiating dense infestations in the laboratory, at least at moderate and high temperatures. Under optimal conditions the infestations develop within 15 days. Values deduced for the pre-adult period at various temperatures were similar to those obtained by Rilett (1949). At 17°C., development was extremely slow but the low temperature did not increase mortality. Cannibalism and competition by adults and fully developed larvae appear to play an important part in limiting the production and survival of the juvenile stages.

Sound grain at 70 per cent. R.H. is unsuitable as a medium for culturingCryptolestesin the laboratory but it becomes suitable after relatively small additions of flour and damaged grains. At 33°C. at least, a point is suddenly reached where an infestation is initiated, the critical feature being increased survival of larvae rather than an increase in the number of eggs laid. An increase in humidity has a similar effect to adding food.

Estimates of the production of CO2at various temperatures gave values higher than previously reported. From 21 to 33°C. the rate of increase of the respiration rate and the increase in the speed of development are proportional to rise in temperature. This is in accord with other indications thatC. ferrugineushas a high optimum temperature.
Experiments on the control of frit fly,Oscinella frit(L.), on late-sown oats with seed dressings and ‘late’ sprays
Authors: Legowski T. J. , Gould H. J.
Published: July 2009

In plot trials with seed dressings on late-sown oats against shoot attack by frit fly,Oscinella frit(L.), chiefly near Cambridge, England, γ BHC, parathion, dieldrin, heptachlor, Rogor and WL 1650 (Telodrin) (1,3,4,5,6,7,8,8-octachloro-3a,4,7,7a-tetrahydro-4,7-niethanophthalan) (dry and wet) reduced the attack but the effect was variable and for the most part not appreciable.

In 1952 and from 1956 to 1960, trials were made on the effect of late sprays of various insecticides applied to late-sown oats when symptoms of frit-fly attack were already conspicuous and sometimes severe. An advantage of this type of treatment over preventive sprays is that it ensures that the treatment is applied only where and when necessary. Single sprays of parathion, dieldrin, γ BHC and Rogor prevented or markedly reduced further attack and they were most effective when applied within about 15 days of the beginning of egg-laying and when plants were in the young seedling stage. Compared with the best treatment of two early preventive sprays of DDT there was only a slight reduction in yield. Parathion and to lesser extent γ BHC killed many larvae inside the shoots and probably prevented others from entering the shoots.
A simple method for breeding the house-fly, Musca domestica vicina Macquart, in the laboratory
Authors: Tharumarajah K. , Thevasagayam E. S.
Published: July 2009

Coconut poonac, the cake left over after the extraction of oil from coconut pulp, has been used very successfully for breeding Musca d. vicina Macq. in the laboratory in Ceylon. The fly lays its eggs in the poonac and the larvae live and pupate in the same medium.
The control of the coconut pest Melittomma insulare (Coleoptera, Lymexylidae) in Seychelles.
Authors: Nye I. W. B.
Published: July 2009

The larvae of the Lymexylid beetle, Melittomma insulare Fairm., bore into the bases of coconut palms. Associated with them are micro-organisms which cause extensive rotting of the bole, particularly at ground-level, and this results in the palm falling.

During 1953–58, an attempt was made in Praslin Island, Seychelles, to obtain maximum control of this pest using paradichlorobenzene as a fumigant. At the time of this treatment, 77 per cent, of the 90,500 coconut palms in the island were infested. Of these, about five per cent, were felled as worthless mountainside palms and nine per cent, fell during or within a week of treatment.

In 1960 it was found that a further 15 per cent, of the palms had fallen and of those still standing 53 per cent, remained infested. The continuing high loss of palms after treatment was due to the closed, moist fumigation chambers within the trunks encouraging the spread of rot, coupled with an incomplete kill of larvae.

A new method of treatment is described in which the necrotic wood is excised and a formulation of coal tar creosote and coal tar liberally applied. Praslin Island was retreated, using this tar method, and a plan to treat all the coconut palms in Mahé, the main island of the group, was subsequently commenced. Losses of palms during and within a week of treatment have been reduced to less than one per cent., and results are quoted which show that a single treatment can reduce a serious infestation in which 80 per cent, of palms are more or less heavily attacked to one in which only 18 per cent, of the palms are attacked and, on average, contain only five larvae. The treatment ensures that the entrances to the tunnels of these are exposed to view, and accordingly the surviving larvae can easily be killed.
A morphological study of variation in Tyrophagus (Acarina), with particular reference to populations infesting cheese
Authors: Robertson Phyllis L.
Published: July 2009

The difficulty of deciding the systematic status of variations within and between populations of Tyrophagus is considered in relation to the wide distribution of the genus and the many materials it infests.

Variation within populations of what was thought to be one species infesting cheese is explained by the isolation of three closely similar forms which it is difficult, if not impossible, to separate by measurement alone. Frequency distributions overlap slightly for four linear measurement ratios on which separation is attempted, but differences between them are emphasised by differences in minute structural characters and they are therefore accepted as distinct species, identified as longior (Gervais, 1844), palmarum Oudemans, 1924, and putrescentiae (Schrank, 1781).

Variation between populations attacking plant materials and other stored products in addition to cheese is accounted for to some extent by the recognition of three further Tyrophagus species, oudemansi Robertson, 1959, brevicrinatus Robertson, 1959, and tropicus Robertson, 1959.

Within the species recognised, significant differences are recorded in dorsal hair characters and body proportions between populations on cheese produced in different geographical areas, and also between cheese populations and those infesting other materials, and these differences are thought to be at a racial level.

T. longior, T. palmarum and T. putrescentiae are found to be distributed around the world, but as cheese pests they occupy somewhat different, although overlapping, geographical zones, since longior is a temperate-to-cool form, palmarum a temperate form and putrescentiae a subtropical or tropical form. The three are also found to occupy different, but overlapping ecological zones, making possible their association in mixed populations.

Confusion in ecological data previously published on Tyrophagus is thought to be attributable in part to similarities in the morphology, geographical distribution and ecology of its species, and to their close association.
The susceptibility of tsetse flies to topical applications of insecticides. I.—Young adults of Glossina morsitans Westw. and chlorinated hydrocarbons
Authors: Burnett G. F.
Published: July 2009

Solutions of six chlorinated-hydrocarbon insecticides in kerosene have been applied in drops of about 0·02 microlitre (µl.) to adults of Glossina morsitans Westw., 2–5 days old, one day after the first meal. This species is found to be unusually susceptible to this group of insecticides. In order of increasing toxicity they are: DDT and aldrin, γ BHC, dieldrin and endrin, Telodrin (1,3,4,5,6,7,8,8-octachloro-3a,4,7,7a-tetrahydro-4,7-methanophthalan). The LD50 of DDT was 0·0165 µg. (males) and 0·025 µg. (females), that of Telodrin was 0·00062 µg. (males). Susceptibility of the two sexes to DDT, γ BHC and dieldrin did not differ significantly. Two batches of flies tested with an interval of eight months differed by about two times in their response to dieldrin and γ BHC; but the response to DDT was unchanged. This difference was not seasonal.

For practical use, dieldrin is the best and cheapest available insecticide, a fact confirmed in the field. Only Telodrin might replace it.
Observations on the biology and control of the cabbage stem weevil, Ceutorhynchus quadridens (Panz.), on trowse mustard (Brassica juncea)
Authors: Winfield A. L.
Published: July 2009

During 1958–60, replicated insecticide trials were carried out in East Anglia in an attempt to assess seed losses on Trowse mustard (Brassica juncea) caused by larval infestations of the cabbage stem weevil, Ceutorhynchus quadridens (Panz.). The overwintered adult weevils invade the young growing crops during April and May, and the eggs are laid in the petioles over a period of weeks, depending both on temperature and crop stage, until about mid-June. Egg-laying began on mustard when the plants had produced six to seven broad leaves, but the actual time at which the first eggs were laid seemed to depend mainly on temperatures during May. In the insecticide trials, infestations averaged up to 26 larvae per plant, and none of the untreated plants entirely escaped attack.

High rates of γ BHC (5 or 10 per cent, of the weight of seed) gave some control of stem-weevil larvae when kerosene was used as the sticker for the insecticide; 3 per cent, or 5 per cent, phorate and 5 per cent. Telodrin (1,3,4,5,6,7,8,8-octachloro-3a,4,7,7a-tetrahydro-4,7-methanophthalan) gave no control. The control by seed dressing was unreliable and is considered unsuitable for assessing yield losses caused by stem weevil.

A single emulsion spray of dieldrin applied during May when the first adult feeding holes were found in the petioles, gave a good control of stem weevil and prevented egg-laying, and this technique seems promising for future work on damage assessment. It is thought, however, that sprays specifically directed against stem weevil would seldom be justified economically on commercial crops of Trowse mustard, but on April-sown crops the first dieldrin spray against blossom beetle, Meligethes aeneus (F.), may give some protection against stem weevil.

The damage-assessment experiments gave no reliable indication of the effects of the stem weevil on yields of seed, in spite of their being sited in localities known to have a high weevil population. It was clear, however, that sowing date greatly influenced yields of seed; plants sown in March outyielded those sown in April or early May.
Studies of the sampling of Glossina pallidipes Aust. III.—The hunger stages of male flies caught on cattle and in Morris traps
Authors: Smith I. M. , Rennison B. D.
Published: July 2009

When non-teneral male flies of Glossina pallidipes Aust. were caught concurrently on oxen and in Morris traps in two experiments in south-eastern Uganda and classified, within 1½ hr. of capture, according to a modification of the hunger-stage categories described by Jackson, individual recorders were found to differ markedly in their assessments. No conclusions regarding the hunger stage of flies taken by different attractants could therefore be drawn from the first experiment, but in the second, which was so designed as to discount possible bias amongst recorders, the proportions of ‘hungry ’ (stage III + IV) flies in catches of males were similar on variously coloured individual oxen, and generally higher than in trap catches, in which the proportions varied widely. As all the traps appeared identical, no generalisation is possible about the mechanism by which non-teneral male flies are attracted to and induced to enter such traps.
Studies of the sampling of Glossina pallidipes Aust. IV.—Some aspects of the use of Morris traps
Authors: Rennison B. D. , Smith I. M.
Published: July 2009

Experiments carried out in south-eastern Uganda, as part of a series of investigations of factors affecting the catch of Glossina pallidipes Aust. by Morris traps, showed that this was not significantly affected by varying the interval between emptying the traps within the range 1½-24 hours or by varying the width of the entrance slit from ¼ to 1½ inches. Such exceptions as occurred could be attributed to unexplained variations in the intrinsic performance of individual traps. Almost no flies were trapped at night (1830–0630 hr.).

Catches in traps with simulated defects (leaving the sleeve open or making holes in the cage gauze) were lower than in perfect traps; the catch was not significantly affected by the diameter of the sleeve opening, but was significantly lower in traps with 16 ½-in. holes in the cage gauze as against those with 2, 4 or 8. Escapes through such holes were observed whilst emptying the traps, when the recorder's approach disturbed the trapped flies, which were otherwise inactive. Frequent visits to the traps to empty them did not materially increase the number of flies effectively trapped, as might have been expected were flies escaping continuously or were the traps to catch flies accompanying the observer.

When the interval between emptying traps exceeded 24 hr., losses of trapped flies occurred, to an extent that is unknown but sometimes substantial, as a result of predation by ants; this is the most likely source of significant variation in catches made by apparently identical traps, and can be overcome by mounting traps on greased, single legs. When thus protected, there was no significant difference in catch between traps cleared at intervals ranging from 12 hr. to eight days. The longer this interval, the greater the proportion of dead amongst captured flies; the median length of life after capture was about two days, this period varying slightly with sex and more substantially with undefined differences between sites and trapping periods.
Field infestation of cowpea (Vigna unguiculata) pods by beetles of the families Bruchidae and Curculionidae in Northern Nigeria
Authors: Prevett P. F.
Published: July 2009

An account is given of a study of infestation of cowpea pods in the field in Northern Nigeria by the weevil, Piezotrachelus varius (Wagn.), and the Bruchids, Bruchidius atrolineatus (Pic) and Callosobruchus maculatus (F.). Oviposition by Bruchids did not commence until the pods were fully formed and light green in colour, whilst infestation by P. varius originated in the young pods. Observations indicated that a high level of parasitism of Bruchid eggs occurred, but that the majority of Hymenopterous parasites emerging from within the pods were related to P. varius.

When pods were harvested at regular intervals, large numbers of P. varius emerged from the early harvests only. B. atrolineatus was the predominant Bruchid species emerging, particularly from early harvests. In the case of a single final harvest of pods, large numbers of P. varius, and a higher level of infestation by B. atrolineatus than in pods collected at regular intervals, were recorded.

Shelling of four batches of pods indicated a mean of 11 per cent, of seeds attacked by Bruchids in the case of single final harvests, and a mean of only 3·5 per cent, in the case of regular harvests as pods became dry. It is concluded that a considerable improvement in quality would result from an adoption of the latter method by farmers, provided that some method of control in respect of the harvested pods were introduced.

From the observations made it is concluded that P. varius is a true field pest, B. atrolineatus primarily a field pest able to continue infestation in store to a very limited extent, and C. maculatus primarily a store pest able to commence its infestation in pods in the field and to build up in numbers rapidly during the immediate post-harvest storage period.

The normal manner of cultivation precludes the use of field methods of control at oviposition peaks but observations suggest that elimination of secondary hosts of P. varius and B. atrolineatus might be worthwhile. A reduction in oviposition by C. maculatus by treatment of stored cowpeas in growing areas, and treatment of pods during the immediate post-harvest storage period, should considerably reduce the level of infestation by this species.
The histochemistry of the cholinesterases in the central nervous system of susceptible and resistant strains of the house-fly,Musca domesticaL., in relation to diazinon poisoning
Authors: Molloy Frances M.
Published: July 2009

The distribution of cholinesterases hydrolysing acetyl- and butyrylthiocholine in the brain and thoracic ganglion ofMusca domesticaL. was examined histochemically in untreated flies, and in flies poisoned with diazinon (O,O-diethyl 0–2–isopropyl–4–methyl–6–pyrimidinyl phosphorothioate) of both susceptible and resistant strains.

The inhibition of cholinesterase after poisoning was, to a greater or lesser extent, confined to the peripheral region of the ganglia, and to other specific areas such as the suboesophageal ganglion and lamina ganglionaris. The extent of inhibition increased with increasing doses of poison, and increasing time after treatment. The degree of inhibition could be broadly correlated with the condition of the fly; badly affected or moribund flies having less active cholinesterase than living and unaffected flies. Together with these areas of more or less complete inhibition were other areas, especially in the neuropile or synaptic regions, in which there remained large amounts of active enzyme. Active enzyme was still present in these areas 24 hours after apparent death of the fly. Total inhibition of cholinesterase throughout the central nervous system was rarely seen, even after very high doses of diazinon causing over 99 per cent. kill.

Inhibition did not occur in the ganglia of living flies of a diazinon-resistant strain after a dose which caused inhibition and death in the normal susceptible strain. With 25 times this dose, causing approximately 99 per cent, kill in the resistant flies, cholinesterase was inhibited in them also, although to a somewhat lesser extent than in the susceptible flies given a comparable lethal dose.

The data provided strong evidence that if death is caused by inhibition of cholinesterase of the nervous system it is due to local inhibition and not to generalised inhibition.