bluuebunny/crossref_metadata_2025 huggingface dataset:
Piperonyl Butoxide as a Constituent of Heavy-oil Sprays for the Control of Stored Product Insects
Authors: Hewlett P. S.
Published: July 2009

The effect of piperonyl butoxide (PB) on the toxicities of allethrin, DDT, and BHC in a heavy oil base to Tribolium castaneum beetles has been tested. PB synergised allethrin and BHC both in films and direct sprays. It antagonized DDT in films, but left the toxicity of DDT unchanged in direct sprays.

The effect of PB on the joint toxicity of BHC and pyrethrins to T. castaneum was also investigated, applying the materials as direct sprays. The data were not so conclusive as had been hoped, but they indicated strongly that in a mixture containing all three materials the PB synergised each insecticide as though the other were absent, i. e., it synergised both simultaneously.

The experimental findings of the present paper are examined in conjunction with the findings of Hewlett and Plackett (1950). It is shown that there is an underlying similarity between the film and direct spray results for the joint toxicities to T. castaneum of pyrethrins, DDT, BHC, and PB, taken in pairs.
Some Observations on resting Tsetse-fly Populations, and Evidence that Glossina medicorum is a Carrier of Trypanosomes
Authors: Nash T. A. M.
Published: July 2009

Further studies were made of G. medicorum and G. fusca using the resting-haunt technique.

During 5½ collecting days, 200 G. medicorum and G. fusca were taken by the resting-haunt technique ; over this period, only one fly was taken by the normal, human bait technique.

Out of 119 G. medicorum 45 per cent, were females, and out of 73 G. fusca, 44 per cent, were females ; the resting-haunt technique yields a good cross-section of the tsetse population.

Out of 15 recently gorged G. medicorum and eight G. fusca examined, all contained mammalian blood. Gorged flies were very numerous, so that it should be possible to ascertain the wild hosts by the precipitin test.

From the evidence available, it is believed that at the end of the rains both G. medicorum and G. fusca feed only during the twilight hours, or when the forest is fully illuminated by the moon.
Note on Damage to Grazing by Grasshoppers in Kenya
Authors: Le Pelley R.
Published: July 2009

A development of grasshoppers to minor plague proportions over a limited area of the Rift Valley near Lake Elmenteita occurred in 1950. The two chief species concerned were Gastrimargus brevipes Sj. and Caloptenopsis glaucopsis meruensis Sj. but many other genera and species were present and are listed. The distribution of rain with appreciable falls followed several times by dry spells may have been a factor contributing to the increase. An unusual increase of the Coccinellid, Epilachna hirta (Thnb.) also occurred in the area a month or two before.
Some Factors affecting the Availability of Contact Insecticides
Authors: Barlow F. , Hadaway A. B.
Published: July 2009

The physical state of deposits from various formulations of insecticides applied to different materials is considered in relation to the availability of the insecticide to insects making contact with the surface of the treated material.

Applications of oil solutions of insecticides to absorptive material result in absorption of the solution, and the insecticide is thereby rendered ineffective. On a nonabsorptive surface, oil solutions are the most efficient formulations, but only so long as the deposit remains wholly or partly liquid; if evaporation of the solvent gives a dry crystalline residue, this is much less efficient than the original solution.

On some fibrous absorptive surfaces, a solution of DDT in oil remains in a supersaturated condition in and around the fibres. If crystallisation is stimulated by mechanical means, the resulting crystals project from the treated surface and it is suggested that, in these circumstances, crystals are more readily available to insects than the oil solution from which they were derived.

DDT on compressed wall board shows the induced crystallisation to a greater degree than other insecticides. It is concluded, therefore, that wall board and similar surfaces should not be used in comparing the potencies of chlorinatedhydrocarbon insecticides applied as oil solutions, as DDT would be more available than others. Some factors that affect the degree of induced crystallisation are mentioned.
Entomological Problems of Food Storage in Northern Nigeria
Authors: Howe R. W.
Published: July 2009

In Nigeria, shelled groundnuts are stored in sacks in covered warehouses and as pyramids in the open air. At the beginning of storage the nuts comprise approximately equal quantities of whole, split and broken nuts of a moisture content of 3·4 per cent. The sacks are exposed to direct hot sun whilst stacking.

The mean monthly maximum shade temperature in Kano ranges from 101°F. in April to 85°F. in January and August and the mean monthly minimum from 75°F. in May to 56°F. in January. Monthly maximum relative humidities range from 100 per cent, in August and September to 45 per cent, in February, and the monthly minimum from 71 per cent, in August to 12 per cent, in February. The range of mean relative humidity is 81 per cent, in August and 18 per cent, in February. Rains fall between April and September, 70 per cent, falling in July and August. Heavy falls are recorded on about 25 days.

Inside warehouses, the maximum monthly temperatures are 102°F. in May and 79°F. in January and February, and minimum temperatures are 81°F. in June, and 58°F. in February. In August the mean relative humidity range is 93 per cent, to 70 per cent. In December it is 34 per cent. to 20 per cent.

Just under the roof of a warehouse and on the surface of pyramids the diurnal range is very large.
The Insects associated with Export Produce in Southern Nigeria
Authors: Cotterell G. S.
Published: July 2009

The problem of insect infestation of stored export food commodities in southern Nigeria is discussed, and a list of insects is given. At the ports there is considerable cross-infestation between commodities produced in northern and southern Nigeria awaiting shipment.

Old sacks used for the storage and transit of groundnuts are responsible for the spread of insects to palm kernel and cocoa marketing centres in the south. After bulk shipments of a portion of the groundnut crop, sacks are repaired and distributed for the shipment of palm kernels and some of them may be used by fanners and brokers as service bags for the marketing of cocoa and local food commodities. The importance of disinfestation before distribution is realised, and a small fumigation plant is in operation at port.

Ephestia cautella and Lasioderma serricorne are the major pests of stored cocoa beans. Both originate in farmers' and brokers' stores which are rarely cleaned, and in which small parcels of low-grade beans may be retained for mixing with a following crop to conform with an exportable grade. Ephestia cautella also infests palm kernels, and the early abundance of adult moths in cocoa stores up country during the marketing season is considered to be largely due to the storage of palm kernels in the vicinity. The development of Ephestia larvae can be completed on the outside of cocoa beans, only germinated or damaged beans being penetrated.
The Effect of a Difference in Temperature and Humidity on certain Reactions of Female Aëdes aegypti (L.)
Authors: Parker Alec H.
Published: July 2009

Sir Rickard Christophers (1947) working at 25°C. and a relative humidity of 80–90 per cent. found female Aëdes aegypti to be attracted by a warm dry surface at 40°C., and to be unaffected by a moist surface at room temperature. The writer (1948), working at 28°C. and 50–70 per cent. R.H. (usually near 50 per cent.) found the opposite: a warm dry surface at temperatures from 36°C. to 40°C. had no effect, while a moist surface at room temperature exerted a quite definite attraction. The purpose of the present experiments was to test the hypothesis that the difference between the results obtained in these two investigations was due to the difference in the ambient temperature and humidity.

Repetition of the relevant experiments at 25°C, 85–90 per cent. R.H., and 28°C, 50–55 per cent. R.H., gave results indicating that temperature and humidity difference operating at the time of the experiment could account for part but not all of the discrepancy. There are indications that the remainder may have been a result of the conditioning effect of temperature and humidity differences operating on the insect prior to the experiment.

The results emphasise the need for a full description of the climatic conditions under which behaviour work of the type discussed is performed.
Studies of British Anthomyiid Flies. VII.—The Onion-Fly Complex
Authors: Miles Mary
Published: July 2009

Onions are attacked by larvae of Anthomyiid flies from May to August. Two species are concerned, namely the onion fly, Delia antiqua (Mg.), and the bean seed fly, D. cilicrura (Rond.). The onion fly, which in some seasons is mainly univoltine, attacks the crop in June and July. The bean seed fly, which has. 3–4 generations a year, is most injurious to spring-sown onions in May and to summer-sown onions in August. Attack by D. antiqua is the result of the chemotropic response of the species to its host-plants. Attack by D. cilicrura follows the disturbance of the soil during cultural operations in April-May, and occurs again when seed-beds are prepared for August sowings.

The recognition of this complex pattern of attack makes it necessary to reconsider the value of established control measures. The calomel (mercurous chloride) seed-dressing is unlikely to give control of onion fly because its ovicidal efficiency is impaired by exposure to the air during the three months between the sowing of onion seed (end of February) and oviposition (end of May), and by the growth of the plants, which results in the eggs being laid at some distance from the old seed-coat which carries the ovicide. It is also unlikely to have a direct effect on infestation by bean seed fly, because the eggs of this species are not necessarily laid on the seedlings and, in the case of August sowings, the eggs may have hatched before the seed is sown.
Abnormalities exhibited by Mosquito Larvae collected in Tonga
Authors: Laird Marshall
Published: July 2009

The duplication of a clypeal spine and the bending of some of the hairs of an antennal tuft in a fourth-instar larva of Culex (Culex) annulirostris Skuse, and the gross malformation of the antennae and siphon of an apparently younger larva from the same pool, are described and discussed.
A second Experiment on testing the reative Efficiency of Insect Traps
Authors: Williams C. B. , French R. A. , Hosni M. M.
Published: July 2009

The paper describes the layout and analysis of a test of two types of insect light-trap, the Rothamsted and the Robinson, and two types of illumination. The layout consisted of four variations of the sequence of six nights X A B O D D (X being a night of no trapping and A-D the four traps) in each of four sites in a small woodland. At the end of a complete cycle of 24 nights there had been four nights without trapping; each trap had been an equal number of times in each site; and each trap had followed all four trap-types, and also no-trapping, an equal number of times. The complete cycle was repeated four times at intervals between May and September. All insects captured were sorted into orders and counted and each order was analysed separately. By analysis of variance (after transforming the numbers caught to a logarithmic scale) it was possible to show separately the effect of differences, (1) between nights, (2) between sites, (3) between types of trap, (4) between types of light, and, (5) between cycles, and also the effect (if any) of the previous night's trapping. It was found that ultra-violet light was more efficient for all orders than ordinary electric light, that the Robinson type of trap was more efficient for the larger Lepidoptera but much less efficient for the small Diptera, but that there was no regular effect of the previous night's trapping. The largest source of variation was the difference between nights: difference between locations was small.
Pseudotheraptus wayi, a new Genus and Species of Coreid (Hemiptera) injurious to Coconuts in East Africa
Authors: Brown E. S.
Published: July 2009

A new genus, Pseudotheraptus, is described for a Coreid bug, Ps. wayi, sp. n., Causing early nutfall of coconuts in East Africa. Two other species, Ps. devastans (Dist.) and Ps. ugandae, sp. n., are placed in this genus, with descriptions and a key for determination of the three species.

The taxonomic relation of Pseudotheraptus to other genera is discussed, with particular reference to Theraptus, in which the species now described as Ps. wayi was formerly placed provisionally, and to Amblypelta, of which one species (A. cocophaga China) is the cause of identical damage to coconuts in the British Solomon Islands Protectorate.

A key is given for the determination of the two species now remaining in the genus Theraptus.
Three new Coccids (Hemipt.: Coccoidea) attacking Coffee in East Africa
Authors: De Lotto G.
Published: July 2009

Australian workers have been interested for some time in the common Ceroplastes on coffee in Kenya as a source from which parasites of Ceroplastes destructor Newst. might be obtained.

The doubt that more than one white waxy scale occurs on coffee in East Africa led to an examination of material of C. destructor and certain other allied species. It was found that C. destructor was present in Uganda and Kenya but did not occur on coffee in Kenya, so far as is known at present. C. brevicauda Hall, here raised to specific rank, was found to occur on coffee in Uganda and a new species, C. luteolus, on the same crop in Kenya.

Descriptions of C. luteolus, Lecaniodiaspis erratica and Pseudococcus latipes, spp. n., all from coffee, are given.
The Transmission of Bancroftial Filariasis on Ukara Island, Tanganyika. I.—A Geographical and Ecological Description of the Island with an annotated List of Mosquitos and other Arthropods of medical Importance
Authors: Smith A.
Published: July 2009

A description is given of Ukara Island, which lies in the Tanganyika part of Lake Victoria, with an annotated list of mosquitos and other arthropods of medical importance found there. There are also notes on local plants and vertebrates.

The inhabitants, called Bakara, live in cone-shaped grass huts over 20 ft. in height and diameter. People and cattle are housed together.

The area of the island is about 45 sq. miles. The 17,000 inhabitants, almost entirely African, support themselves by advanced agricultural practices involving the use of manure and nitrogenous plants. There is a coastal belt of intense cultivation and a large central area of uninhabited grassland with extensive deep erosion. The beds of rivers which radiate from the centre are occupied by large irrigated areas. Seasonal fluctuations in lake level have little effect in general on cropping practices which are affected more by seasonal variations in rainfall.

The average rainfall for 1950–52 was 62 inches per annum. Temperatures are equable throughout the year. Mean maxima for 1953 were 81°F. for April, 83°F. for May, 82°F. for June and 81°F. for July—mean minima were 70°F. for April, 68°F. for May, 69°F. for June and 67°F. for July. Wind velocities, recorded at noon, vary between 4·8 metres per second in June and 2·4 in January.
The Transmission of Bancroftial Filariasis on Ukara Island, Tanganyika. II.—The Distribution of Bancroftial Microfilaraemia compared with the Distribution of Hut-haunting Mosquitos and their Breeding Places
Authors: Smith A.
Published: July 2009

Ukara Island was selected for studies on the transmission of bancroftial filariasis because it provided a naturally circumscribed area with a substantial human population of which adequate numbers showed miorofilariae. It is a closely-knit and stable community.

Filarial infections also occur in bird, lizard, dog and hyrax (rock-rabbit) on the island. The determination of the vectors of human filariasis thus depends on evidence of different kinds, the present paper considering only the general correlation of microfilarial incidence with the distribution of common domestic mosquitos in villages of the island.
The specific Biological Characteristics ofAnopheles(Myzomyia)sergentii(Theo.) and their Correlation with Malaria Control in Israel
Authors: Saliternik Z.
Published: July 2009

Anopheles(Myzomyia)sergentii(Theo.) has been shown to be the most important vector of malaria, especially ofPlasmodium falciparum, in Israel at the present time.

The morphology of the adults, larvae and eggs is discussed, details being given of variations in the pigmentation of the fronto-clypeus in the larvae, a factor the possible genetical significance of which is felt to warrant further research.

Resistance of the aquatic stages to extreme variations in environmental conditions and their ability to survive and even metamorphose in minimal amounts of water have been observed. Breeding in nature has been found between 12°C. and 36°C. At 30°C. the time elapsing from egg-laying to hatching is one and a half days. Pupal development takes a further one and a half days and the total time from oviposition to the emergence of the adult is nine days, whereas in winter it may be as much as three months.
Cuticular bands as age criteria in the sheep blowfly Lucilia cuprina (Wied.) (Diptera, Calliphoridae)
Authors: Tyndale-Biscoe Marina , Kitching R. L.
Published: July 2009

In Lucilia cuprina (Wied.), cuticular bands are deposited most clearly on the mesothoracic post-phragmata, and up to ten such layers can be counted. The bands are deposited clearly only in response to fluctuating temperatures where the minimum temperature in a cycle falls below about 15·5°C. Growth bands are deposited whenever such a change in ambient temperature occurs and the deposition appears to show no inherent rhythmicity. The maximum width of the phragmata is more or less constant and the number of bands which can be distinguished depends upon how quickly the maximum width of the phragmata is reached. The rate of growth of the growth bands and their consequent width depends upon the maximum temperature experienced and the length of time the insect is maintained at that temperature in any cycle. Trials showed that the count of growth bands was an acceptable estimate of the actual age in days when temperatures rose 3·5°C or more above the threshold value of 15·5°C. With a greater temperature range, greater accuracy was achieved. The availability of protein food was shown to have little effect on the deposition of growth bands. A mean age in days was calculated for samples of field-caught flies of a uniformly young ovarian ‘age’ using the counts of growth bands and by working back in the temperature records from their sites of capture using the day-degrees method. Significant differences between the two estimates of age were taken to indicate the occurrence of developmental delays. These were attributable to shortages of protein food in the field and were associated with periods of drought. The method allows the demonstration that developmental delays have occurred but does not provide an accurate estimate of the duration of these delays. It does not permit the confident identification of delays imposed by shortages of oviposition sites.
Digestive processes of haematophagous insects. VII. Comparison of animal-fed and membrane-fed adults of Glossina morsitans morsitans Westw. (Diptera, Glossinidae)
Authors: Gooding R. H.
Published: July 2009

An Agar/Parafilm membrane system, developed for feeding tsetse flies, was evaluated by comparing membrane-fed and goat-fed female Glossina morsitans morsitans Westw. with respect to the following: fly weight, meal size, trypsin levels and amount of protein in the posterior midgut, and the portion of midgut protein which is in the posterior midgut. In flies having the same prefeeding history, the digestive physiology of membrane-fed flies was not significantly different from those fed on goats. The offspring of membrane-fed flies were lighter, took smaller meals, and had less trypsin and protein in the posterior section of the midgut than did flies from the stock animal-fed colony. However the relationship between trypsin levels and protein in the posterior part of the midgut was the same in flies from animal-fed and membrane-fed colonies.
A new species of Psychodopygus Mangabeira (Diptera, Phlebotomidae) from the Transamazônica highway, Pará State, Brazil
Authors: Fraiha H. , Ward R. D.
Published: July 2009

A new species of sandfly, Psychodopygus lainsoni, is described from specimens captured in ‘ terra firme ’ rain forest at km 46 Altamira-Itaituba on the Transamazônica highway. In many respects the male resembles those of the squamiventris group, and the female is similar to those of other groups.
Field and laboratory observations on Psychodopygus lainsoni Fraiha & Ward and other sandflies (Diptera, Phlebotomidae) from the Transamazônica highway, Pará State, Brazil
Authors: Ward R. D. , Killick-Kendrick R.
Published: July 2009

Descriptions are given of the collection and rearing of Psychodopygus lainsoni Fraiha & Ward and five sympatric species, P. carrerai (Barretto), a member of the P. squamiventris group, Lutzomyia anduzei (Rozeboom) and two undescribed species closely related to L. anduzei (Rozeboom) designated L. sp. no. 260.43 and 260.44, all from the Altamira region of the Transamazônica highway, Pará State, Brazil. Fungal contamination of rearing containers and a reluctance of reared flies to feed prevented the establishment of closed colonies of these silvatic species. Storage of P. lainsoni eggs at 15°C delayed hatching, and reduced hatch rates and larval viability. Pupal storage at 12°C failed to inhibit emergence. Diapause is reported in the egg stage of L. sp. 260.44.
The retardation of puparium formation in Diptera: could factors other than ecdysone control cuticle stabilisation inGlossinaandSarcophagaspecies?
Authors: Whitehead D. L.
Published: July 2009

Evidence gained using blowflies (Calliphora vicinaR.-D.,Lucilia sericata(Mg.),L. cuprina(Wied.) andProtophormia terraenovae(R.-D.) ), fleshflies (Sarcophagaspp.) and tsetse flies (Glossinaspp.) in ligaturing experiments and by the injection of prepupal haemolymph (with added ecdysone) suggests that factors other than ecdysone, released in the posterior segments, may initiate pupariation. They could act as synergists for ecdysone. Puparium formation is reduced from 77·5±3·1% to 35·7±2·8% (P<0·001) if 50 ng α-ecdysone is injected through the anterior knot into the middle region of twice-ligaturedSarcophaga argyrostoma(R.-D.) larvae instead of into the abdomens of singly tied larvae. The pupariation score is increased to 57·2±4·8% if haemolymph from rounded-off prepupae is injected into the middle region of isolated abdomens. The uninjected posterior region sometimes darkens alone. Ligature of the abdomens ofS. peregrinaR.-D. andS. argyrostomaprepupae which have just reached the orange-peritreme stage before rounding-off confines the pupariation to the posterior segments.

The effects of retarding puparium formation for 12–24 h by the use of dopa decarboxylase inhibitors or by means of a loose constriction (‘ cummerbund‘) are reported because the location of the patches of cuticle which stabilise and darken as the inhibition slowly wears off implicates certain areas under the integument as the sites of production or secretion of puparial tanning hormone or ‘ posterior darkening factor ’. Retardation of pupariation results from the pressure stimulus applied to rounded-off prepupae because either a hormone is held back or an inhibitor is released as a consequence of the distortion of the cuticle by the cummerbund. When fleshfly larvae are tightly ligatured every hour in front of or behind the brain for 18 h after removal from a moist environment which inhibits pupariation, the percentage of larvae which pupariate in both situations suggests that the CNS itself can inhibit pupariation of the anterior region because of the presence of the stricture. This inhibition, which is not due to lack of oxygen, can be reversed by the presence of factors produced in the abdomen.
Estimated mortalities of the immature stages of Aedes cantans (Mg.) (Diptera, Culicidae) in a natural habitat
Authors: Lakhani K. H. , Service M. W.
Published: July 2009

For three consecutive years the eggs, the immature stages and the emergent adults of Aedes cantans (Mg.) populations were sampled from a small woodland ditch in southern England with a view to constructing the life-table of the species. Estimates of the numbers of ‘viable’ eggs available for hatching and the size of the resultant adult population yielded an estimate of the probability of a ‘viable’ egg resulting in an adult. Estimating the mortality rates in different immature stages which occur simultaneously is known to be difficult. It was considered reasonable to rely on a generalised exponential survivorship model based on the assumption that the relative mortality rate during the duration of each instar of A. cantans is constant, but this rate may vary from instar to instar. The parameters of the model were estimated using experimental data on the duration and total incidences through regular sampling of different instars together with the estimate of the probability that a ‘viable’ egg would result in an adult. The survivorship picture thus obtained agreed closely with the survivorship pattern obtained using a graphical approach based on the construction of the stage-specific age distribution of the pre-adults, and then drawing a smooth curve through the age distribution to produce an approximation to the survivorship curve. Because mortality was similar in all three years, the three years' data were pooled to give estimates of the life-table parameters. These clearly showed that substantial population loss occurred in the first two larval instars of A. cantans.
Biology and host specificity of two aphids Dactynotus chondrillae (Nevsk.) and Chondrillobium blattnyi (Pintera) (Hemiptera) living on Chondrilla juncea
Authors: Caresche L. A. , Hasan S. , Wapshere A. J.
Published: July 2009

The biology and host specificity of Dactynotus chondrillae (Nevsk.) and Chondrillobium blattnyi (Pintera) living on the weed Chondrilla juncea (Compositae, Cichoriaceae) have been studied in the Mediterranean region as part of the biological control programme against this weed for Australia. Both are recorded from south-eastern Russia to the western Mediterranean region. The two species are monoecious. D. chondrillae has a facultative sexual reproductive phase every year but Chondrillobium blattnyi reproduces indefinitely by parthenogenesis in the Mediterranean region. D. chondrillae feeds mostly on young shoots, has population peaks in the spring and in the autumn, and can damage Chondrilla in the field. Chondrillobium blattnyi is a leaf feeder capable of seriously injuring the rosettes, but it never occurs in large enough populations in nature to be damaging. To demonstrate specificity, both aphids were tested against various Cichoriaceae and other Compositae and also against 61 cultivated plant species belonging to 20 families. The two aphids were shown to be specific to the genus Chondrilla. In the laboratory D. chondrillae was less host restricted than the other aphid and it reproduced on Sonchus asper and Taraxacum officinale. Comparative testing with strains of the two aphids from various sources against various forms of C. juncea showed that each strain was adapted to the form of C. juncea occurring in its own geographic area. The southern French strain of these aphids was ill-adapted to the main Australian form of C. juncea, but a strain of D. chondrillae originating from the Italian Adriatic coast heavily infested this form. D. chondrillae was not considered to be specific enough to permit its introduction into Australia and the introduction of Chondrillobium blattnyi has been delayed until it can be shown that it cannot transmit virus diseases that affect lettuce.
The biology of the Psylloidea (Homoptera): a review
Authors: Hodkinson I. D.
Published: July 2009

Psyllids are generally narrowly host specific and are restricted almost exclusively to perennial dicotyledenous plants. Psyllids are known vectors of plant diseases. In addition, the effects of salivary injection can be very severe, causing growth abnormalities in the plant. Psyllid development rates are related to the nutritive status of the host-plant and, as in aphids, the honeydew produced while feeding is low in nitrogen. Psyllids reproduce sexually and pass through five nymphal instars before becoming adult. The immature stages exhibit both morphological and behavioural adaptations to resist desiccation, and the life-cycle is often highly synchronised with host-plant phenology. Adult Psyllids are known to disperse up to eight miles on wind currents, although in general dispersal is less marked than in aphids. The mechanism of host-plant selection is probably chemo-gustatory. Capacity for population increase in Psyllids is more dependent on generation time than on female fecundity. Recorded Psyllid parasites include Diptera of the family Cecidomyiidae and a wide range of Hymenoptera. These parasite species are almost exclusively parasitic on Psyllids although there is little evidence for parasite–host specificity within the Psylloidea. Psyllid species from a wide range of geographical areas have similar predator complexes. Anthocorids, Syrphids, Coccinellids and Neuroptera larvae are the main predators. At high population densities nymphal mortality increases in a density-dependent manner with increasing density, whereas at low densities nymphal survival is enhanced by group feeding. Close parallels exist in the feeding biology of aphids and Psyllids, but aphids appear better adapted for the exploitation of unstable ephemeral food sources.
The chemical inhibition of feeding by phytophagous insects: a review
Authors: Chapman R. F.
Published: July 2009

Chemical inhibition of feeding has been studied in detail for only a few insect species, but inhibitory chemicals play a considerable part in host-plant selection by a wide range of phytophagous insects from several orders. Many different chemicals are involved, some of them amongst the normal constituents of plants. A few have a general effect, preventing feeding by all the insects which have so far been tested, but the majority are effective only against some species.

Inhibition may function by blocking the input from receptors normally responding to phagostimulants or by stimulating specific ‘deterrent’ cells. The former may have a general effect on all insects, but chemicals in the latter category will only be effective if the insect has neurones capable of responding to them. Hence these will have more specific effects.

Inhibitory chemicals may be applied to plants in the same way as insecticides, their advantage being that the parasite/predator complex of species not feeding directly on the plant will be unharmed. An alternative approach is to breed resistant varieties of plants by selecting for inhibitory attributes. Although many varieties of crops are known which are insect-resistant, the basis of the resistance is generally unknown. A more thorough understanding of the mechanisms involved in inhibition of feeding by chemicals would enable a more logical approach to be made to the development of resistant plants.
The maintenance of laboratory colonies of Culicoides variipennis (Coq.), C. nubeculosus (Mg.) and C. riethi Kieff. (Diptera, Ceratopogonidae)
Authors: Boorman J.
Published: July 2009

A method is described by which Culicoides variipennis (Coq.), C. riethi Kieff. and C. nubeculosus (Mg.) have been maintained as laboratory colonies for over five years. Techniques are given for the maintenance of adults, larvae and pupae; with some modifications these could probably be applied to a range of other species. Adult midges were held in waxed card pill boxes, and provided with sugar solution. Anaesthetised mice provided a blood-meal source. Larvae were reared in pans on a substrate of glass fibre in a medium which contained nutrient broth, grass meal and Bemax. The life-cycle of these species occupies 10–21 days at 23–25°C.
The arrival of male moths of the cotton leaf-worm Spodoptera littoralis (Boisd.)(Lepidoptera, Noctuidae) at a new continuously recording pheromone trap
Authors: Campion D. G. , Bettany B. W. , Steedman R. A.
Published: July 2009

A pheromone trap is described which records the exact time individual male moths enter a trap. This apparatus was operated for approximately three months at two sites in Cyprus. Continuous recordings were made of wind speed, wind direction, temperature and relative humidity near the trap site. Males of Spodoptera littoralis (Boisd.) were generally attracted to a trap baited with S. littoralis virgin females for the first two to three hours after dark. Males of S. exigua (Hb.) arrived most frequently at a trap baited with S. exigua females between 03.00 and 04.00 h. A relationship between wind speed and numbers of males of S. littoralis recorded was found at one site; for winds at a height of 1–37 m varying between 0·8 and 5·2 m s-1, increased wind speed resulted in an increase in the numbers of males recorded. Increase in relative humidity at one site was associated with a decrease in the number of males recorded. No apparent relationship was established between temperature and the number of males recorded, other than the fact that below 13°C many fewer males arrived at the trap. The implications of these findings in relation to movement of adult male S. littoralis are discussed.
Disruption of embryonic development by juvenile hormone and its mimics in Dysdercus fasciatus Sign. (Hemiptera, Pyrrhocoridae)
Authors: Wall C.
Published: July 2009

The embryonic development of Dysdercus fasciatus Sign. is described in terms of 15 arbitrary stages based on external morphological characters. The effects of treating eggs early in development with juvenile hormone and a mimic (JH) are then described in terms of the stages at which embryonic development is arrested and the resulting morphological aberrations are summarised. The effects of the treatment of two strains of D. fasciatus with two JH (Law's mimic and Ayerst synthetic juvenile hormone) are described and compared in terms of both the hatchability of the eggs and the stage distributions of the arrested embryos. Law's mimic was more effective than Ayerst SJH in preventing egg hatch, and the Malawi strain was less susceptible than the Reading strain. Embryonic development was never arrested earlier than the commencement of blastokinesis (Stage VIII). After treatment with Ayerst SJH most embryos of both strains were arrested during dorsal closure (Stages XI-XII) or at the time of eclosion (Stages XHI-XIV). Treatment of the Reading strain with Law's mimic resulted in the majority of embryos being arrested during blastokinesis (Stages VIII-X) at all doses. Examination of the timetable of development in both control and treated eggs reveals a dramatic reduction in developmental rate in treated eggs at the commencement of blastokinesis. It is suggested that JH may act on eggs of D. fasciatus in three ways: interference with eclosion, differentiation and the embryonic movements during blastokinesis.
The subgenus Larroussius of Phlebotomus (Diptera, Psychodidae) in the Ethiopian region
Authors: Lewis D. J. , Minter D. M. , Ashford R. W.
Published: July 2009

The subgenus Larroussius of Phlebotomus includes several vectors of visceral leishmaniasis. A key is given for the tropical African species, three of which are described for the first time. Notes on the species include a discussion of the status of P. langeroni orientalis Parrot, one of the three species from the Ethiopian Region known to transmit leishmaniasis.
Methods of Automatic Collecting for Studying the Fauna of the Soil
Authors: Trägårdh Ivar
Published: July 2009

When studying the fauna of the soil it is obviously of the utmost importance to use such methods of collecting the animals as are thoroughly reliable and efficient, so that one can be reasonably sure of getting practically all the animals existing in a given material. It is not to be expected that one method will ensure successful collection of all the animals, because some react in one way towards the agents chiefly used, viz., strong light and heat, others react in another way. For instance, some animals, such as Tardigrades and Rhizopoda, encyst themselves when subjected to dryness and cannot be forced to move downwards away from the light and dryness as most arthropods do. As pointed out by the author (1928) all methods of mechanically separating the animals from the substratum by sieves, etc., are worthless unless applied to larger animals such as Oligochaeta, larger beetles and snails. For all smaller animals the only safe method is the automatic one based on their reactions towards light and dryness, which was devised by the late Professor A. Berlese in Florence in 1905.

This apparatus is so well known that it is not necessary to give a detailed description of it, nor need I dwell on the more or less similar apparatus constructed later, except Tullgren's, because the latter, constructed in 1917, has been used by several investigators. Tullgren substituted the funnel filled with water and heated by gas, which Berlese used for the purpose of drying the material containing the micro-arthropods to be collected, by an electric bulb suspended above the material in a cylindrical funnel at a distance of about 5 cm. above the material.
Gall Midges (Cecidomyidae) as Enemies of Mites
Authors: Barnes H. F.
Published: July 2009

This is a third of a series of papers dealing with zoophagous gall midges of the world. The first, “ Gall Midges as Enemies of Aphids,” was published in 1929 (Bull. Ent. Res., xx, 1929, pp. 433–442) and the second, “ Gall Midges as Enemies of the Tingidae, Psyllidae, Aleyrodidae, and Coccidae,” appeared more recently (op. cit., xxi, 1930, pp. 319–329).

In this paper the species of gall midges whose larvae have been reported as preying on mites are dealt with, the first reference mentioned being in each case that of the original description or record. Practically all the literature available consists of specific descriptions and little is stated about the bionomics of the species with a few exceptions. It is a matter for regret that such scant attention has been paid to this aspect of biological control, especially in view of certain statements claiming that the larvae of various gall midges are of considerable importance in the natural control of red spider. It is with a view to stimulating further research in this direction that the present paper has been compiled.

It has been thought advisable to divide the paper somewhat arbitrarily into separate sections, dealing firstly with those species of gall midges preying on free-living mites and secondly with those species preying on gall-inhabiting mites. A further section deals with those Cecidomyids which may feed on mites. As an additional convenience, a list of plants on which the mites live is appended. The Cecidomyids which may be predacious on mites (see section 5) are not, however, included in this list.
Notes on the Natural Control ofColeophora laricella, the Larch Case-bearer
Authors: Thorpe W. H.
Published: July 2009

This paper consists of a preliminary report on investigations of the parasites ofColeophora laricellain Europe, with a view to their possible utilisation in Canada.

Systematic and biological notes on the more important species are given.

The most promising parasite,Angitia nana, has already been shipped to Canada. It is a solitary internal parasite of the case-bearer larva. Further investigations are necessary before it can be considered safe to introduce any other species.

I am very grateful to Dr. C. Ferrière, of the Imperial Institute of Entomology, for the time and trouble he has given to the work of identifying the parasite material. The late Mr. J. C. Robbins helped materially by kindly carrying on observations while I was absent through illness, and by collecting material in the field. Mr. R. J. Spittle has been of great assistance in the production of the finished drawings, several of them being mainly his own work. A number of the earlier field collections were made by Mr. H. S. Hanson.
Observations on Glossina morsitans, Westw., in East Africa
Authors: Potts W. H.
Published: July 2009

1. Methods used in the production of pupae of G. morsitans, Westw., in the laboratory have been described.

2. Observations, based on the pupae produced in the laboratory, have been recorded on larviposition, pupation, pupal period and stages of pupal development.

3. The pupal period was found to vary with the temperature, from 23·1 days when kept constantly at 86°F., to 48·5 days at a varying temperature, the mean noon temperature during development being 70·0°F.

4. Examination of puparia collected from natural breeding-sites showed that there is a fairly heavy mortality in the pupal stages in nature, amounting in some cases to as much as 50%.

5. Parasitisation by the Hymenopterous parasite, Syntomosphyrum glossinae, was found to a very slight degree—0·2& only.

6. Heavier parasitisation by three species of Bombyliids—Thyridanthrax abruptus, T. lineus, and T. argentifrons—occurred.

7. The living, dead, and parasitised puparia could be distinguished by (a) immersion in methylated spirit of S.G. 0·820, when those sinking would be alive, and (b) subsequent immersion in petrol of those floating in methylated spirit, when those sinking would for the greater part be parasitised and those floating would be dead.

8. The degree of temperature lethal to pupae was found to depend on duration of exposure. Thus, whereas pupae survived exposure to 55–57°C. for 2 minutes, 45–50°C. was lethal when the exposure lasted half an hour, whilst even 40°C. was lethal when continued for 4 hours or more, and pupae failed to survive 13 days at 35°C.
Traps for Tsetse-flies of the “ Crinoline ” and “ Ventilator ” Forms
Authors: Chorley C. W. , Swynnerton C. F. M.
Published: July 2009

Prefatory Note.

Having had the privilege of seeing something of Mr. Chorley's very fine work against Glossina palpalis, and having had four of his traps (of the types shown in Pl. xi, figs. 1, 2, 5) in experimental use myself, I would like to state that he has, in my opinion, done particularly excellent service in evolving several good types of trap for this tsetse-fly. They have not been properly tested yet against other species of tsetse. The choice of exactly suitable sites for the traps, as with all tsetse-traps, is a matter of considerable difficulty and demands expert knowledge, but if skilfully sited, the traps catch well. They represent the acme of cheapness. The mere tacking of a skirt on a Conical Hoop Trap (1912), a Hughen's trap (1919) or a Barrel Trap (Burnett 1918) makes a “ Chorley ” Trap for tsetse-fly. A mere sack or trouserleg kept open by a hoop and with a non-return cage on the top suffices ; and the trap collapses, like a lady's dress, into no space at all. It is simply, in some of its forms (as in Pl. xi, figs. 1, 2, 5), a very slight adaptation to tsetse of Richmond's Crinoline Trap for mosquitos, published in 1927 in the Government of India's Health Bulletin, No. 11 ; in its “ ventilator ” forms (e.g., fig. 3), it is an adaptation of the Wahl & du Plessis trap for blow-flies, published in 1923 in the Journal of the Department of Agriculture of South Africa—though even here the form most used has been cylindrical.
Further Observations on Dysdercus superstitiosus, F., and other Insects affecting Cotton in Southern Nigeria
Authors: Pomeroy A. W. J.
Published: July 2009

Young bolls may be shed owing to the mechanical action of stainer puncturing, apart from the introduction of any specific internal boll disease. One puncture is sufficient to obtain this effect.

Unless the carpel wall is pierced, no injury to the boll from insect attack results, and it is highly probable that the piercing of the carpel wall is essential for the introduction of internal boll disease.

Internal proliferation does not take place unless the carpel wall is pierced, and is not an essential factor in the shedding of young bolls, but rather an indication of injury from an external source.

Puncturing by stainers of the buds and flowers, before the flower petals have fallen off, may cause the shedding of the boll and the introduction of internal boll disease.

The surest superficial diagnosis of stainer injury to bolls, as compared with other insect injuries, is the finding of a bead of moisture exuding from the single minute orifice, in the case of a fresh puncture, and of a minute canal in the centre of the corked area of an injury some days old. The regularity of the rim of the corked area is a strong indication of stainer injury, the periphery of the corked area produced by the nibbling of young Lepidopterous larvae being irregular, owing to the action of the mandibles.
Observations on the Ability of Larvae of Anopheles maculipennis, Mg., to crawl
Authors: Nikolsky V. V.
Published: July 2009

My observations in 1923, and more particularly in 1924, made both in nature and in the laboratory, have proved that larvae of Anopheles maculipennis, Mg., are able to crawl quite actively and, under certain conditions, may wander from one pool to another.
The Food of the Red-billed Oxpecker, Buphagus erythrorhynchus (Stanley)
Authors: Moreau R. E.
Published: July 2009

The Red-billed Oxpecker, or Tick-bird, is the East African representative of a genus that has always excited interest by reason of the peculiar feeding habits of its members. They obtain the whole of their food on the bodies of the larger Herbivora, and their abnormally sharp claws permit them to travel in any direction and to visit every spot on the bodies of their hosts. It is obvious that to stock-owners birds of these habits must be of economic importance, but veterinary, ornithological and entomological literature alike have failed to provide any record of an investigation of their food.

In the absence of published data application was made to various authorities for their opinions and for any detailed information they might have. Astonishingly diverse replies were given. The head of a veterinary laboratory in one of the East African dependencies wrote as follows : “ I believe they do pick off ticks, although I doubt if they eat these ; their object being to find a wound. When they have succeeded they feed on the exposed raw tissue.” Another local veterinary authority remarked : “ They cause a great deal of damage through the sores they produce in stock.” A gamewarden said : “ I always regarded the oxpecker as an unmitigated nuisance and pest. The prevalent idea that this bird frees domestic stock of ticks appears to be entirely erroneous.… These birds feed mainly on the raw tissue of open wounds and it is by their action that the open wounds usually occur.” Other observers of wide experience are less downright.