bluuebunny/crossref_metadata_2025 huggingface dataset:
An Experimental Campaign with Light Aircraft against Flying Locust Swarms in New South Wales
Authors: Casimir M.
Published: July 2009

A campaign in New South Wales against flying swarms of the Australian Plague Locust, Chortoicetes terminifera (Wlk.), using Tiger Moth light aircraft, is described. Large rolling swarms of this locust, travelling across the open plains of western New South Wales, are directed in their general south-easterly move ment by natural barriers in such a way that regular migration routes are followed and predictions of swarm movements can be made. Of particular importance are the timber fringes of creeks and rivers which tend to baulk swarms temporarily and it was in such situations that locust swarms proved most susceptible to treatment by a manoeuvrable aircraft.

A technique of drift spraying was developed wherein aircraft were able to operate without ground direction against travelling swarms by spraying at right- angles to the wind direction and by using the main body of the flying locusts for demarcation. Large numbers of short spraying runs were made in rapid succes sion over the most dense portions of the swarm being treated until control was achieved. It was found that the spacing of the runs was not particularly important as long as each was applied to the densest portions of the swarm. The light and relatively slow-moving Tiger Moths proved highly suitable for this work and they were also useful for scouting and keeping track of swarms. Observations made after spraying indicated that the coherent flying swarms treated in the open plains were almost completely eliminated. If, however, swarms were able to reach closely settled or heavily timbered areas they tended to split and disperse and were difficult to treat. The insecticide used was an emulsifiable concentrate containing 7 per cent. γ BHC, which was diluted with diesel oil, and one gallon of liquid containing 5·6 oz. of γ BHC was designed to cover one acre. However, as the campaign progressed, effective use of the spray was probably obtained at less than one gallon per acre, and a total area of 30–37 square miles of dense swarms was treated at a cost of approximately £13,700. There is scope for an improvement in the efficiency of the spraying technique as well as a reduction in some of the major costs in any future campaign.

It was considered that the campaign carried out in the Ivanhoe—Hillston district completely controlled all swarms in the area and protected from invasion valuable farming lands to the south-east. Further spraying operations, in the Jerilderie district, 150 miles away, were less successful, although many mor locusts were killed. The spraying party arrived in the district too late to plah a strategic campaign and some swarms escaped treatment.

It is concluded that the method of aerial drift spraying is capable of wider application in Australia, particularly in areas where problems of distance, popula tion and lack of facilities militate against successful control by ground machinery.
Injury to Cacao by Amblypelta Stål (Hemiptera, Coreidae) with a Summary of Food-plants of Species of this Genus
Authors: Brown E. S.
Published: July 2009

Evidence is given, based on, field observations and experiments, of damage to fruits of cacao by two species of Amblypelta (A. theobromae Brown in New Guinea and A. cocophaga China in the British Solomon Islands); the nature of the damage is described.

A summary is given of the feeding habits generally, and the effects on the plants attacked, of members of the genus Amblypelta.

Comprehensive lists of the known food-plants of each species of Amblypelta are given.
Progress in the Biological Testing of Sorghum Midge (Contarinia spp.)
Authors: Barnes H. F.
Published: July 2009

Successful emergence of examples of Contarinia sp. and associated parasites has been obtained at Rothamsted Experimental Station from midge-infested heads of sorghum received from India (Mysore State) and West Africa (Ghana).

Since typical pre-mating behaviour was observed on all of the few occasions when newly emerged males and females from the two continents were confined together, and actual mating was obtained between a male from Ghana and two females from Mysore in rapid succession, it is concluded that inter-mating will take place under suitable environmental conditions, although in the present series of experiments such conditions were rarely present.

It has not yet been possible to test the fertility of such inter-matings or to prove biologically that the species of Contarinia concerned is the C. sorghicola (Coq.) of Texas, although on morphological grounds there are apparently no reasons for their separation.

Two species of parasites, a Tetrastichus sp. (group of flavovarius, auct.) and Eupelmus popa Gir., were reared from the Indian material, and another species of Tetrastichus (group of flavovarius, auct.) and E. popa were reared from the West African material.
Systematic Notes on Species of Callosobruchus of Economic Importance
Authors: Southgate B. J.
Published: July 2009

The Cowpea Weevil, Callosobruchus chinensis (L.), has been distributed by commerce and now breeds throughout most of the tropics and sub-tropics, although in the southern part of Africa it is replaced by C. rhodesianus (Pic). The systematics of both species are discussed and redescriptions given of them and of C. subinnotatus (Pic), formerly regarded as a variety of Bruchus vicinus Gylh., together with an account of the genitalia of both sexes, and Tables distinguishing the first two species from one another and the third from the closely related species, C. maculatus (F.).
The Effect of Lizards on the Biological Control of Scale Insects in Bermuda
Authors: Simmonds F. J.
Published: July 2009

In an intensive study, begun in 1955, on the biological control of Pseudaulacaspis pentagona (Targ.) and Pulvinaria psidii Mask. on oleander (Nerium oleander) in Bermuda, several species of COCCINELLIDAE were successfully established, but none developed a population sufficient to control either scale. The failure of these apparently suitable species of Coccinellids was therefore investigated. It seemed possible that insectivorous lizards, which are very abundant everywhere, might be responsible.

Dissection of a number of lizards, Anolis grahami, and A. leachi, in the autumn and winter indicated that at both these times their effect on the natural enemies of scale insects in general and of Pseudaulacaspis pentagona and Pulvinaria psidii in particular, was considerable. Both Coccinellids and Hymenopterous parasites were eaten in large numbers. A surprising number of very small insects including ants, was eaten, and although a number of the insects eaten are harmful, on balance it would appear that, particularly with regard to the biological control of scale insects, the elimination from Bermuda of these lizards, which are introduced species, would be beneficial.

Experiments are being carried out to test this, and the introduction of predacious birds, particularly that of the Trinidad kiskadee, Pitangus sulphuratus, is planned.
Rearing and Culturing Musca sorbens Wied. in the Laboratory
Authors: Hafez Mahmoud , Attia M. A.
Published: July 2009

Several artificial media were tested in an attempt to eliminate the use of human faeces as oviposition and early larval habitats for breeding Musca sorbens Wied. in the laboratory. Eggs, laid on cotton-wool pads moistened with diluted milk or, preferably, on small quantities (10–15 g.) of human excrement, were transferred to the breeding medium. The best of those tested was a mixture of coarse wheat bran (120 g.) and diluted milk (240 g.), which yielded normal healthy larvae and adults. The average weight of a puparium produced in this medium was somewhat less than that of one produced in human excrement.
Inheritance of Aldrin Resistance in the Indian House-fly, Musca domestica nebulo F
Authors: Abedi Zille Hasan
Published: July 2009

The inheritance of aldrin resistance in the Indian house-fly, Musca domestica nebulo F., was studied by making reciprocal crosses between individual as well as groups of flies of an aldrin-resistant and a non-resistant strain of the subspecies at 28±1°C. The offspring of all the families thus formed were tested by the topical application of constant-volume drops of various concentrations of aldrin solution in oil to the dorsum of thorax of groups of flies. Mortality counts were made 24 hours after treatment. The results obtained indicated a multifactorial heredity for aldrin resistance in M. d. nebulo. The phenomenon was found not to be sex linked.
Reactions of Insects to the Olfactory Stimuli from the Components of an Insecticidal Spray
Authors: Hocking B. , Lindsay I. S.
Published: July 2009

Two kinds of equipment for measuring the reactions of insects to the olfactory stimuli provided by some common components of insecticidal sprays are described. One of these, consisting of a T-tube carrying a current of odorous air across the top and admitting insects up the stem, is new, can be used in the field, and gives rapid and reproducible evaluations. Tests with several species of Diptera showed that technical DDT, diesel fuel oil, and an auxiliary solvent containing methylated naphthalenes are all strongly repellent or contain strongly repellent components. Related species gave similar results with the two kinds of equipment. House-flies (Musca domesticaL.) resistant to DDT were less sensitive than normal house-flies. The implications of these findings are discussed.
Effects of the Ant, Lasius niger (L.), on the Behaviour and Reproduction of the Black Bean Aphid, Aphis fabae Scop
Authors: Banks C. J.
Published: July 2009

Cage experiments confirmed that, in the absence of natural enemies, populations of Aphis fabae Scop., attended on bean plants (Vicia faba) by the ant, Lasius niger (L.), multiply more rapidly than otherwise similar but ant-free populations. The average difference in numbers recorded, was about one-third, the maximum being 70 per cent. No doubling or trebling of aphid numbers as claimed by an earlier worker was ever recorded.

When the Aphids are attended by ants, their excretion behaviour alters and the normal dispersal of the apterae from the young apical growth of bean plants is considerably delayed.

No significant differences were found between the numbers of nymphs produced by individual Aphids from ant-visited and ant-free plants, respectively, living on leaves of the same age; but the numbers were significantly affected by the age of the leaf or part of the plant on which the Aphids had developed or were then feeding.

It is suggested that ant-attended aphid populations multiply more rapidly because most of the Aphids feed for a much longer time on young plant tissue where, presumably, their food supply is more nutritious.
First Results in the Control of Simulium damnosum Theobald (Diptera, Simuliidae) in Northern Nigeria
Authors: Crosskey R. W.
Published: July 2009

An experimental control project against Simulium damnosum Theo. in Northern Nigeria using DDT in diesel oil as a larvicide is described. A description, together with a map, is given of the project area, some 1,200 sq. miles in extent, with a population of 32,000 persons, and it is emphasised that this was selected to provide information on the feasibility of control in an area not isolated from other fly foci.

Methods used in applying the larvicide to the rivers, which had rocky beds with rapids and falls, and assessing the effects of treatment are discussed. Applications were made at prearranged treatment points, weekly, for a period of 12 weeks in the dry season of two successive years, 1956 and 1957, and the post-treatment density of adult fly was assessed and compared in a Table and in histograms, with that existing in the year prior to treatment.

In the first year, a mean dosage per application of 1·4 p.p.m. of p,p′DDT applied over 30 minutes (S.D. = 0·5 p.p.m.) at each of four treatment points resulted in the clearance of all breeding for a distance of 15–23 miles below these points, and a reduction of adult fly density in the area of 96 per cent. as compared with pre-treatment density. But reinfestation of cleared breeding grounds was found to be rapid, these becoming repopulated with immature stages within six months in spite of a mean wet-season fly density of only 0·35 flies per boy-hour.

In the second year, with application of 1 p.p.m. of p,p′DDT for 30 minutes, results were less successful than in the first, although three additional treatment points were used with the aim of controlling a greater distance than in the first year, adult density being only reduced by an estimated 82 per cent. of that before treatment in the first year. The reasons for this are discussed, and the lower degree of control is attributed to the partial failure of the insecticide to reach the breeding sites owing to the exceptionally low state of the rivers.

The fly-rounds used in assessing adult density and the pre-treatment breeding sites and the positions of the treatment points are shown on maps. Detailed data from the fly-rounds are given in an Appendix.

With the exception of slight mortality among fish, thought to be due to accidental impediments to tbfi free downstream flow of the larvicide, no toxic effects on other organisms were observed.

The cost of treatment is given, and the results are discussed briefly in relation to the existing knowledge on control of S. damnosum. It is suggested that control by the application of larvicides in non-isolated foci is a practicable possibility, but that annual treatment might be necessary because of rapid re-establishment in cleared areas. The effect of control, of the degree obtained in this work, on the incidence of human onchocerciasis cannot yet be determined.
The Behaviour of Larvae ofCulicoides circumscriptusKieff. (Dipt., Ceratopogonidae) towards Light Stimuli as influenced by Feeding, with Observations on the Feeding Habits
Authors: Becker P.
Published: July 2009

The larvae ofCulicoides circumscriptusKieff. are mostly negatively phototactic when extracted from mud and placed in water. Experiments show, however, that if kept without food over a period of time a large proportion becomes positively phototactic. The provision of food causes them to revert to a photonegative taxis which may be permanent as long as suitable food is given, or temporary if the food does not satisfy their nutritional requirements. On the other hand, the provision of a completely non-nutritive medium does not bring about such a reversion. The significance of this behaviour is discussed in the light of the habits of the larvae in the field.

Most of the experiments were carried out with batches of fourth-instar larvae, but in a few, third-instar larvae and fourth-instar larvae near to pupation were used. From the results it is suggested that the processes of ecdysis and pupation may bring about a reversal from photonegative to photopositive taxis independent of the need for food.

The significance of the behaviour of the larvae towards light stimuli is discussed in relation to their habits in the field. It is assumed that its function is to maintain the larvae on the surface of the mud while feeding and to drive them below when they have fed, and that some other type of tropism must initially drive them to the surface or keep them below according to their nutritional needs.

It is shown that the behaviour towards light stimuli of the larvae ofC. maritimusKieff. differs somewhat from that ofC. circumscriptusand reasons are suggested for this.

A second series of experiments designed to throw some light on the food requirements of the larvae is described. In a discussion on the results of these it is shown that the larvae feed on material both on the surface of the mud and below the surface, and it is suggested that larvae which have fed on sub-surface food become positively phototactic when they require food from the surface and, having fed there, revert to photonegative behaviour. If, however, photopositive larvae have not previously had the opportunity to feed on sub-surface material they continue to act as completely starved larvae and remain photopositive in spite of their having fed on surface material.

The detailed constituents of the larval diet have not been worked out. The larvae appear to be detritus feeders, feeding mainly on vegetable matter and bacteria obtained on or below the surface of the mud, though green algae are not an important part of their diet. They are carnivorous on occasion but are normally not so when other food is readily available. They are selective in their choice of food and at least three factors, sapidity, texture and the size of particles, appear to influence this selection.
A Survey of the Build-Up of Infestation in Bagged Cocoa Beans in Store in western Nigeria
Authors: Riley J.
Published: July 2009

Two tons of cocoa, in 32 bags, stacked in a typical cocoa store in Ibadan, Nigeria, were sampled from December 1953 to the end of April 1954. The weekly catches on “ até “ strands hung round the stack suggested that Ephestia cautella (Wlk.) was the most numerous insect on cocoa, but spear samples of the beans, taken from the sacks every two weeks, showed that the actual population of this species in the beans was small throughout the season, with no sign of build-up. Lasioderma serricorne (F.), on the other hand, was shown to be the most serious pest, the population in the beans increasing steadily from an extremely low level. It is estimated that on the average it is not safe to store initially good cocoa for more than 25 weeks in the main crop season.
Insecticidal Action Studies with Demeton-O and Demeton-S
Authors: David W. A. L.
Published: July 2009

The two isomers demeton-O and demeton-S which occur as a mixture called demeton in the commercial insecticide Systox act on Aphis fabae Scop. as contact and systemic insecticides and as fumigants.

When applied as a contact insecticide or systemically via the roots from solution or from soil, demeton-S was about ten times as toxic to Aphis fabae on broad beans as demeton-O. Using demeton-S containing 32P it was shown that, when applied to the roots, radioactive material passed to all parts of the plants and that the concentration in the aerial parts was higher than in the roots. Leaf samples were more active than stem samples. By radioassay and by the cut tap-root technique it appeared that the lethal dose of demeton-S was equivalent to about 1·0 mg./kg. of fresh plant tissue. The lethal dose of demeton-O by the cut tap-root technique was 3·0 mg./kg. From solutions, the plants first absorbed demeton-S preferentially, then water preferentially. Demeton-S was more rapidly absorbed from sand than from soil.

Both isomers were translocated from older to younger leaves of broad beans usually in sufficient quantities to kill Aphids but the results were more consistent with demeton-S. The quantity translocated downwards was small. A low light intensity before and after treatment reduced the quantity of demeton-S translocated. There was also a reduction in the quantity translocated when the plants were only shaded before treatment. One day of shading was sufficient to cause the maximum reduction.

Solutions of the two isomers gave off toxic vapours and plants treated via the roots gave off toxic vapours from the foliage.
Observations on Chironomidae at Khartoum
Authors: Lewis D. J.
Published: July 2009

This paper deals mainly with species ofTanytarsus(CHIRONOMIDAE) at Khartoum, particularly the very commonT. lewisiFreeman. These midges are a serious pest there, usually between November and April, causing great annoyance by swarming in vast numbers around lights during the first few hours after sunset and thus interfering with work and pleasure in the riverain area. They are probably responsible for a considerable amount of asthma and other conditions due to allergy. Little information is available about the biology of CHIEONOMIDAE in Africa, so reference is made to the PalaearcticT. mancusWalker, to whichT. lewisiis closely related. Studies of Chironomids from the health point of view elsewhere have little relation to the Khartoum problem, but work onChaoborus(CULICIDAE) is of interest.

The conditions under which these midges occur at Khartoum and the methods of study are described.

At least 26 species of CHIRONOMIDAE, including four ofTanytarsus, occur at Khartoum. The respiratory organs of some pupae are figured, and a key, based on the characters of these organs, is given for some of the species.

Observations on the biology of all stages are recorded, particularly on the vertical movements and drifting of larvae and pupae and the time of emergence. Many larvae and pupae drift downstream at night, andT. lewisiemerges mainly in the early morning.

Some exploratory field trials of larvicides were carried out. The results were inconclusive, and the difficulty of assessing them is pointed out. Thorough control by anti-larval measures would be extremely difficult owing to the large size of the river and the drift of pupae from upstream. It is believed that it might be possible but prohibitively expensive, and would have to be repeated annually, perhaps throughout the midge season. Various protective measures are discussed. It is considered that riverside dwellers who can do so should move inland, and that a barrier of trees parallel to the river would protect houses away from the river front. People who must be near the river in the evening can achieve considerable protection by clearing some vegetation, fogging with insecticide, or using air-cleaning or air-conditioning equipment.
Molecular markers in entomology
Authors: Loxdale H.D. , Lushai G.
Published: July 2009

A diverse range of novel molecular (DNA) markers are now available for entomological investigations. Both DNA and protein markers have revolutionized the biological sciences and have enhanced many fields of study, especially ecology. Relative to DNA markers, allozymes are cheap, often much quicker to isolate and develop, even from minute insects (aphids, thrips, parasitic wasps, etc.), and subsequently easy to use. They display single or multi-locus banding patterns of a generally easily interpretable Mendelian nature, and the statistics for their analysis are well established. DNA markers are also suitable for use with small amounts of insect material and can be used with stored, dry or old samples. They have an expanding range of applications, many involving intra- and interspecific discriminations. Like allozymes, they can be single or multilocus, whilst methods for their statistical analysis have recently been published. However, they can be considerably more expensive than allozymes, require more complex preparatory protocols, expensive equipment, may involve lengthy development procedures (e.g. isolating cloned oligonucleotides to develop primers to detect microsatellite regions) and some have complex multi-locus banding patterns which may be of a non-Mendelian nature (e.g. RAPDs, randomly amplified polymorphic DNA), and are in some cases, not easily repeatable. In this review, we hope to inform the general reader about the methodology and scope of the main molecular markers commonly in use, along with brief details of some other techniques which show great promise for entomological studies. Thereafter, we discuss their applications including suitability for particular studies, the methods used to load and run samples, subsequent band detection, band scoring and interpretation, the reliability of particular techniques, the issues of safety involved, cost effectiveness and the statistical analyses utilized.
Responses to electrified targets and daily activity of Stomoxys spp. (Diptera: Muscidae) in Zimbabwe
Authors: Schofield S.
Published: July 2009

Responses of Stomoxys spp. to electrified targets (1 × 1 m) that differed in pattern and colour were investigated over a three month period at Rekomitjie Research Station, Zimbabwe. In the first experiment, a target baited with a blue and black cloth insert caught more flies (315 ± 117) than a target baited with blue cloth insert (202 ± 69). Next, a blue-cloth baited target caught more flies (491 ± 150) than a black-cloth baited target (164 ± 69) and a target containing a cloth with a black diamond on a blue background caught more flies (997 ± 326) than a target containing a cloth with a black square on a blue background (680 ± 125). Finally, a target fitted with a cloth consisting of a vertically oriented black stripe on a blue background caught almost three times as many flies (1366 ± 356) as a target fitted with a cloth consisting of a horizontally oriented black stripe on a blue background (545 ± 150). Hourly collections of Stomoxys spp. from a blue and black target, baited with and without carbon dioxide, indicated that daily activity was bimodal, with a small morning peak and a large late afternoon peak.
Lunar Rhythm of Emergence, differential Behaviour of the Sexes, and other Phenomena in the African Midge, Chironomus brevibucca (Kieff.)
Authors: Fryer G.
Published: July 2009

Larvae of the African midge, Chironomus brevibucca (Kieff.), are abundant in the littoral zone of Lake Bangweulu, Northern Rhodesia, where, at certain times of the year, imagines emerge in vast numbers shortly after the appearance of the full moon. Attracted by light, the imagines fly to houses and alight on the protective gauze screenings, which, at peak periods of emergence, become covered with a solid mass of midges. They have not been seen at other phases of the lunar cycle, so the adult life is certainly not more than ten days and is usually much less.

Imagines, which are inactive by day, tend to settle in different situations according to their sex. On the gauze screenings there was a marked preponderance of females (4·68:1) on the day following a night's swarming but, on several adjoining whitewashed walls, males predominated (2·92:1). On grasses near the lake margin females outnumbered the males.

When, the gauze screening of a house was diffusely illuminated, imagines were attracted to it during the early hours of darkness. The first flies to arrive were almost invariably males, but females followed on rapidly and finally constituted the bulk of the population. On one evening the percentage of males fell in three hours from 95·4 at 1844 hr. to 29·5 at 2145 hr. The percentage of males reaches a minimum between 1900 and 2000 hr. and thereafter shows some rise, probably due to a secondary influx of males which are thought to have been resting during the day and not to be newly emerged.

An indication of the adult age of males seems to be given by the condition of the antennae during the early part of their adult life.

Some miscellaneous observations on the behaviour of C. brevibucca are recorded.

Some aspects of the phenomena recorded are discussed. The recent hypothesis of Korringa, which seeks to explain the periodíc swarming of certain polychaetes just after the time of full moon as being the result of an additive effect of exposure to nocturnal illumination on the maturation of organisms that are not subjected to sunlight by day, is examined and shown to be applicable to C. brevibucca.
Biology and Ecology of the Garden Chafer, Phyllopertha horticola (L.).
Authors: Milne A.
Published: July 2009

This part of the study of the garden chafer, Phyllopertha horticola (L.), in the English Lake District covers the flight seasons 1948–1952. Annual sex ratios in the population of pupae (just before ecdysis to adult) ranged from 34·6 to 46·9 per cent. females.

The flight season begins with the emergence of some adult males upon the sward. If the weather continues favourable, the earliest females appear on the second or third day of the season. Unsuitable weather delayed the advent of females until the sixth day in two seasons. In a homogeneous population, primary emergence is complete in just under a fortnight, at the end of which time numbers of beetles seen on the grass sward are at their peak. Phase 1, swarming over the sward, continues, with dwindling numbers, for just over a week more (overlapping Phase 2, swarming on the bracken).

The female/male ratio rises throughout Phase 1 except for a tendency to fall in the last day or two. But generally for most and sometimes the whole of Phase 1, the proportion of females above ground is far below the true population ratio. This is partly because population emergence in the female is 1–2 days behind emergence in the male; but much more because after primary emergence the male is fully involved in above-ground activity every day until the beginning of Phase 2 or end of Phase 1 (depending on whether he emerges earlier or later), while the female is not.

In the same way, there are no females present on the bracken until after the first day of Phase 2, but the proportion of females rises more quickly and to a higher level than in Phase 1. By the middle of Phase 2, the proportion is close to the true population ratio. Since males are now confined to the bracken, this means that mass oviposition is more or less complete. During the last week of the season the female proportion rises steeply. This is because females live a few days longer than males besides being 1–2 days behind males in their original emergence.

After primary emergence, the average female lives about a fortnight, the male rather less. Approximately the first half of adult life is spent in the grass sward area, the second half on the surrounding bracken (or hedges or trees).

As Phase 1 proceeds, the pairing rate of females decreases. This is partly because the proportion of males is falling and therefore fewer males are available to search for each female over the grass sward, and partly because of a change in mating behaviour of the female as she ages. On the other hand, pairing rate is at its highest (average 82%, maximum 95%, of available females) in Phase 2 when the proportion of males is at its minimum (actually the true proportion in the population). This is because on the bracken the beetles are confined to a much smaller area than on the grass and therefore males find females more readily.

In flying weather, the proportion of beetles in the air at any moment is at best no more than about 70 per cent.; usually it is less than 50 per cent. On the whole males are very much more given to flying than females.
The Distribution of Shoot-fly Larvae (Diptera, Acalypterae) within Pasture Grasses and Cereals in England
Authors: Nye I. W. B.
Published: July 2009

During the winter months, when larval populations of shoot flies (Diptera, Acalypterae) are relatively static, pure clumps of grasses in southern England were sampled. The tillers were dissected and the shoot-fly larvae removed and identified to determine what species were present and how and in what numbers they were distributed within the species of grasses. Concurrently, a permanent pasture was sampled in which the grasses were closely intermixed, and it was found in the two cases that the same host preferences of the insects were broadly maintained. Those preferences are due to the selectivity of the ovipositing female rather than the dietary requirements of the larvae, which are facultative parasites of most grasses and cereals.

A Table is given of the relative abundance of the larvae of 17 species in 16 different grasses and indicates the degree of host specificity of each insect. For example, Oscinella frit (L.), the frit fly of oats, is found in 11 of the common grasses but not in Dactylis glomerata whereas O. albiseta, (Mg.) is found only in this grass.

Horizontal migration of larvae from tiller to tiller can take place; vertical migration may also take place from ploughed-in grasses to cereals sown above. It is shown that migration is mainly limited to autumn and spring when soil temperatures are above the thermal threshold of activity of the larvae.
Infectibility of Tsetse Flies, Glossina palpalis (R.-D.) and G. tachinoides Westw. with Trypanosoma vivax
Authors: Squire F. A.
Published: July 2009

Observations were made at Dorimon in the extreme north-west of Ghana, during the hot months of March and April 1954, of the infectibility of Glossina palpalis (R.-D.) and G. tachinoides Westw. with Trypanosoma vivax.

Pupae were obtained from the Black Volta where shade temperatures ranged from 70 to 98°F. and the flies that emerged from them were kept singly in small glass tubes in the laboratory at a temperature of 85 to 95°F. and a relative humidity of 60 to 80 per cent. They were given several feeds on infected goats. The following percentage rates of infection were observed.

Labrum and (or) hypopharynx: General rate, 56·1; males of G. palpalis, 72·2, females, 34·6; males of G. tachinoides, 68·4, females, 56·8.

Labrum only and labrum & hypopharynx: General rate, 37·4; males of G. palpalis, 27·8, females, 15·4; males of G. tachinoides, 68·4, females, 40·9.

Early infection is the rule but late infections occurred. Some flies appear to be uninfectible. Thus, out of 107 flies, 47 remained uninfected in spite of having had on the average 10·6 infective meals per fly. A high percentage of flies lost their labrum infection.

The following percentage loss of labrum infection was recorded: General rate, 48.8; males of G. palpalis, 66·7, females, 62·5; males of G. tachinoides, nil, females, 43·8.

G. tachinoides appears to be more tenacious of infection than G. palpalis. Feeding infected flies on goats in the negative phase and (or) on spurwing goose (Plectropterus gambensis) did not appear to have any adverse effect on the colonies of trypanosomes in the labrum.
Observations on the Mosquito Fauna of Mombasa
Authors: Teesdale C.
Published: July 2009

Records are given of the species of mosquitos captured at Mombasa in the years 1943–44 and 1949–52. They were caught by four different methods, namely: (1) day-time net catches in the bush, (2) window-trap catches, (3) diurnal (bait) biting catches in the bush and (4) twenty-four hour (bait) biting catches in three different situations. Sixty-six species were taken in the day-time net catches and nine others which did not figure in the net catches were taken in one or other of the remaining three methods.

The habits of the commonest species, as indicated by these catches, are discussed in some detail.

Culex pipiens fatigans Wied. occurred in large numbers in biting catches, net catches and window-trap catches. In 24-hour catches most biting occurred after midnight, but, in the window traps, activity was greatest between 18 and 21 hr.

Aëdes simpsoni (Theo.) was not taken in window traps or houses. Seasonal occurrence, as indicated by larvae in banana axils, net and biting catches in the bush, is discussed. Twenty-four hour catches confirmed earlier findings that this mosquito bites almost solely during daylight.

Aëdes pembaensis (Theo.) occurred throughout the year with little seasonal variation; this is thought to be connected with its breeding in crab-holes. It is often found in fair numbers in houses when these are near the breeding grounds. Window-trap catches show that most activity takes place at night though some also occurs during the day. The biting rhythm as shown by 24-hour catches in houses, bush and on tree platforms is discussed.

Aëdes albicosta (Edw.). Previously this mosquito may have been confused with Aëdes albothorax (Theo.) and Aë. lineatopennis (Ludl.). It can occur at times in great numbers when it may bite viciously both indoors and outside.

Anopheles gambiae Giles and A. funestus Giles were not evident in large numbers. In window traps most activity took place at night although some also occurred during the day. In 24-hour catches, A. gambiae fed mostly just before dawn though biting occurred also from midnight onwards. A. funestus appeared suddenly and in fair numbers in window traps but was absent for much of the year.

Aëdes aegypti (L.), though fairly common, is recorded only in Tables and in one figure as its bionomics have already been discussed elsewhere.

Notes are given on other species, which include Culex duttoni Theo., C. nebulosus Theo., C. tigripes Grp., Aëdes metallicus (Edw.), Aë. albocephalus (Theo.), Eretmapodites subsimplicipes Edw. and E. quinquevittatus Theo.
Bionomics of the Tea Red Spider, Oligonychus coffeae (Nietner)
Authors: Das G. M.
Published: July 2009

The red spider, Oligonychus coffeae (Nietn.), is the most widely distributed and probably also the most serious pest of tea in north-eastern India, and also occurs on tea in other parts of India and in other countries. It attacks jute, Corchorus capsularis, in India and has been recorded on a wide variety of other plants in India and other countries.

The life-history of O. coffeae in north-eastern India is described. The duration of the life-cycle varies with the season depending on the temperature and humidity.

In May and June the life-cycle is completed in 9·4–12 days outdoors, while in the cold weather it may take as much as 28 days. The maximum length of life of a female has been found to be 29 days indoors. The males usually die within four or five days. Parthenogenetic reproduction may take place under induced conditions, the progeny being all males.

Red spider normally attacks the upper surface of the mature leaves in which the sap is not flowing freely. In a severe infestation, particularly under conditions of dry weather, the lower surface and the young leaves are almost equally attacked. The affected leaves turn brown, then bronze, and may eventually dry up and fall off.

The red spider mites live under a cover of web that they spin as a protection against inclement weather. The pest occurs in severe form from March to June but with the monsoon rains it practically disappears. A second, light, attack may, however, develop in September or October.

During the cold weather, the mites are present in very small numbers on a few old leaves of the tea bushes, and with the rise in temperature in the spring, they multiply rapidly, resulting in subsequent heavy infestations.

Various factors influence the incidence of red spider and the intensity of its attack. Pruned bushes properly cleaned out are less affected. Bushes defoliated after pruning, and medium pruned tea remain practically unaffectsd. Prolonged dry weather during the early part of the flushing season normally increases the red spider incidence. It prefers bright sun and unshaded areas are more severely attacked.

The red spider spreads from bush to bush by crawling. Dispersal is also effected by various agencies such as wind, cattle, goats and labourers.

A number of predatory insects attack eggs and other stages of the red spider, often keeping it considerably in check.
Transect Fly-rounds in Field Studies of Glossina
Authors: Ford J. , Glasgow J. P. , Johns D. L. , Welch J. R.
Published: July 2009

The fly-round has for long been regarded as the most satisfactory way of following fluctuations in populations of tsetse flies (Glossina) and locating areas of concentration. It consists of a path cut through bush so as to traverse the principal vegetation communities and is divided into sections, corresponding to the latter, on each of which the flies are caught. A modification now widely used but not previously described in detail is termed a line transect or transect fly-round; this follows an arbitrary course along straight lines that may be orientated with regard to the topography and is divided into numerous short sections of equal length terminating at posts at which flies are caught. In its simplest form it follows a straight course, but various patterns are used including an angular spiral. It facilitates the collection of quantitative data on tsetse density and the factors (such as vegetation) that affect it, and their analysis is possible in more detail than was the case when the fly-round was laid out according to a pre conceived notion of vegetational relationships. This is illustrated by data from a fly-round at Shinyanga, Tanganyika, consisting of six sides, each of 2,000 yd., of two diagonally adjoining squares, that was divided originally into nine sections of varying lengths representing the floristic communities traversed, and subse quently into 120 sections each 200 yd. long. Comparison of the catches of non-teneral males of G. swynnertoni Aust. grouped according to the two methods emphasises the much greater detail provided by the second of them. The transect fly-round is easy to lay out and operate and is thought likely to be particularly useful in connection with reclamation work.

The effect of varying the section length was investigated for G. swynnertoni at Shinyanga, G. pallidipes Aust. in Nyanza Province, Kenya, and G. austeni Newst. in Zanzibar. With the first, progressively fewer flies of all categories except teneral males were caught as the section length was increased progressively from 50 to 200 yd.; with the other species a similar tendency was apparent, but not significant. The results emphasise a point long recognised but often neglected, that data from fly-rounds reflect, in part, the reaction of tsetse populations to the behaviour of the catching party. That this reaction, termed the availability, is itself inconstant is shown by catches of G. pallidipes on a fly-round done daily for a month, in which differences between catches on consecutive days, sometimes exceeding 3:1, must represent changes in availability, not in absolute population.

Data from the transect fly-round can be analysed so as to indicate sections where the catches deviate significantly from those expected on the assumption that they are distributed according to a Poisson series, and where there may thus be presumed to be areas of concentration of the population, or the reverse. A Table is provided to facilitate such analysis.
The Deposition of Airborne Droplets on dead House-flies (Musca domestica L.)
Authors: Jarman R. T.
Published: July 2009

An experimental laboratory study of the deposition of droplets on dead house-flies (Musca domestica L.) was made, using a spinning-top sprayer to produce a spray of uniformly sized oil droplets and a cascade impactor to measure the concentration of the spray of droplets, which were dyed. The deposits obtained on a dead house-fly and a cascade-impactor slide when these were exposed in turn to a wind of 1 m. per sec. in a wind tunnel were compared colorimetrically, and determinations thus made of the collection efficiency of the flies, defined as the volume of liquid deposited on an object expressed as a percentage of the volume that would have passed through the same cross-section as the object had that not been there.

The measured collecting efficiency of a fly varied from about 70 per cent. (droplet dia. 27μ) to about 200 per cent. (droplet dia. 75μ), and was approximately twice that of a sphere with a cross-sectional area twice the projected frontal area of the fly. From theoretical calculations of the filtering effect of different elements of the vegetation, it is concluded that the optimum droplet diameter for deposition on flies in woodland is 20–40μ.
A New Genus and two New Species of Encyrtidae (Hymenoptera, Chalcidoidea) from the Banana Scab Moth,Nacoleia octasema(Meyr.)
Authors: Eady R. D.
Published: July 2009

The material on which this paper is based was bred fromNacoleia octasema(Meyr.) in New Guinea. The species of the new genus, herein described, was found to be an important primary parasite of the larva. TheTyndarichusspecies is a hyperparasite.

The new genus is close toCopidosomaandLitomastix, and very closely resembles the other genera of this group in both structure and habits. In the species described below the male is not unlike the males of some species ofCopidosoma, and the female resemblesLitomastix; the species appears to be polyembryonic. In the present state of the systematics of the ENcyrtidaeit is deemed advisable to describe this species under a new genus.

I am grateful to Dr. J. Ghesquière, who consented to examine material of this genus and was generous in his advice and assistance.
The Simuliidae (Diptera) of British Honduras
Authors: Lewis D. J. , Garnham P. C. C.
Published: July 2009

Several collections of pupae and adults of Simuliid Diptera were made in British Honduras between 9th January and 18th February 1958. Samples were collected in the Mountain Pine Ridge and El Cayo areas in the west, and along the highway traversing the eastern part of the country between Caves Branch and Stann Creek.

Thirteen species of Simulium were found, nine of which are named, including S. quadrivittatum Lw. and S. metallicum Bellardi which are very annoying biters. A, few observations on distribution and habits are recorded.

Of the two anthropophilic species of Simulium found, one is known to be a vector of onchocerciasis, if only of secondary importance, and the capability of the other to transmit the disease is unknown. The disease has apparently never been established in British Honduras and is present in Guatemala. The risk of infection to settlers moving into territory near Guatemala cannot be assessed without detailed knowledge of the epidemiology of the disease in Central America.
Parasites of Ancylostomia stercorea (Zell.), (Pyralidae, Lepidoptera) a Pod Borer attacking Pigeon Pea in Trinidad
Authors: Bennett Fred D.
Published: July 2009

In Trinidad, the only serious pod borer attacking pigeon peas is Ancylostomia stercorea (Zell.). This species breeds throughout the year. The eggs are laid on the young pods and the larvae feed on the developing seeds and later pupate in the soil. The complete life-cycle requires 26–32 days.

Eight species of parasites were reared from the larvae of Ancylostomia. Life-history studies and rearing techniques for the six commonest species are presented.

Apantelcs etiellae isolatus Mues. is a solitary endoparasite attacking first- to third-stage host larvae. It emerges from the fourth-stage host and constructs a white cocoon in the pod. The life-cycle takes 14–18 days.

Phanerotoma bennetti Mues. is a solitary egg-larval parasite. The egg is laid in that of the host, but the parasite does not complete development until the host has reached the final larval stage and constructed a cocoon. A generation is completed in 20 to 28 days. A method of breeding this species on Ephestia cautella (Wlk.) is described.

Eiphosoma annulatum Cress, is a solitary endoparasite attacking first- to fourth-stage hosts. The parasites emerge from fifth-stage hosts which may be stunted in size but construct normal cocoons. The life-cycle is completed in 26–35 days.

Bracon thurberiphagae (Mues.) and Bracon cajani Mues. are gregarious ectoparasites of similar habit. They paralyse second- to fifth-stage larvae and deposit eggs on or near them. The life-cycle is completed in 13 to 16 days. A method of rearing field-collected immature stages is described.

Perisierola sp. is a gregarious ectoparasite. The adult enters the pod, paralyses a host, and attaches her eggs directly on to the caterpillar. Second- to fifth-stage hosts may be attacked but the larger hosts are preferred. The female frequently remains with her progeny until they have completed their development, which requires 11 to 15-days.

Hyperparasites attacking the parasite pupae are listed.

Details of a shipping container and methods of rearing and shipping parasites to Mauritius for trial against Etiella zinckenella (Treitschke) and Maruca testulalis (Geyer) are described. From a stock of more than 44,000 cocoons so sent two species, Bracon cajani and Eiphosoma annulatum, have been successfully established in Mauritius.
A spear for sampling bulk grain by suction
Authors: Burges H. D.
Published: July 2009

A light-weight spear has been developed to take samples of unlimited size from bulks of cereal grains. The spear is screwed on to lengths of narrow metal pipe, which are used to insert it into a bulk of grain. The sample is sucked out of the bulk through the pipe by the air stream of a domestic vacuum cleaner. This method largely overcomes the disadvantages inherent in other types of spear. The spear can be inserted into a bulk in any direction, even upwards. When sampling downwards, samples can be obtained from as deep as 9 m. Samples can be taken from directly against the walls of a store and as close as 1 cm. to the floor.