Rearing experiments with Trogoderma granarium Everts were conducted to determine why the larvae fail to develop in certain pulses. The larvae were unable to penetrate whole grains of any of the nine pulses tested. In flour form, the pulses fell into three main groups. On flours of green, black, Bengal and kabuli grams, and cowpea and pigeon pea, development was as successful and rapid, or nearly so, as on wheat flour and showed little improvement from the addition of yeast. Development on flours of soybean and lentil was markedly slower, and showed marked improvement when yeast was added. By adding increased proportions of balanced diet, it was shown that the performance of larvae on soybean, lentil and even on French bean flours could be improved, but with the last two was not as good as with cellulose. It is concluded that lentils and French beans lack essential nutrients and may also contain a growth inhibitor.

Triks of the group of Rhipicephalus sanguineus (Latreille) in 423 total monthly collections taken from camels, cattle, donkeys, sheep and goats between September 1978 and August 1979, and in a few miscellaneous collections, from the Yemen Arab Republic were examined. Adult ticks of three species in the group were identified: R. camicasi Morel, Mouchet & Rodhain, R. turanicus Pomerantsev and R. sanguineus s.s. Host relationships and ecological affinities were analysed. R. sanguineus s.s. occurred rarely, only on dogs. R. turanicus occurred on all host species including dogs but more frequently on cattle and camels. It was collected from both dry and wet habitats but was taken regularly at only one wetter site. R. camicasi, the most common species in the group, occurred at most collecting sites on all host species except dogs. Overall, the numbers of R. sanguineus group ticks were low throughout the country and no seasonal patterns could be detected.

The areas in China with climates suitable for the potential distribution of the pest species red turpentine beetle (RTB) Dendroctonus valens LeConte (Coleoptera: Scolytidae) were predicted by CLIMEX based on historical climate data and future climate data with warming estimated. The model used a historical climate data set (1971–2000) and a simulated climate data set (2010–2039) provided by the Tyndall Centre for Climate Change (TYN SC 2.0). Based on the historical climate data, a wide area was available in China with a suitable climate for the beetle in which every province might contain suitable habitats for this pest, particularly all of the southern provinces. The northern limit of the distribution of the beetle was predicted to reach Yakeshi and Elunchun in Inner Mongolia, and the western boundary would reach to Keerkezi in Xinjiang Province. Based on a global-warming scenario, the area with a potential climate suited to RTB in the next 30 years (2010–2039) may extend further to the northeast. The northern limit of the distribution could reach most parts of south Heilongjiang Province, whereas the western limit would remain unchanged. Combined with the tendency for RTB to spread, the variation in suitable habitats within the scenario of extreme climate warming and the multiple geographical elements of China led us to assume that, within the next 30 years, RTB would spread towards the northeast, northwest, and central regions of China and could be a potentially serious problem for the forests of China.

The comparative attractiveness to Glossina morsitans morsitans Westw. and G. pallidipes Aust. of donkeys, cattle, sheep and goats in the presence of wild game was examined during two investigations in a middle-veld area of Rhodesia. Host preferences were assessed by the identification of blood-meals collected in the grazing area. Both cattle and donkeys provided a high proportion of the diet. Sheep and particularly goats were fed upon to a minor degree. The significance of the findings is discussed in relation to tsetse control.

It is noteworthy that the breeding-places of different mosquitos vary with the seasons and that mosquitos are influenced in the selection of their breeding-places by such differences as those of temperature, relative humidity, cloudiness and rain, or alkalinity and food supply, and a further study of the breeding-places of Aëdes (Finlaya) notoscriptus, Skuse, has revealed some interesting details worthy of record. In this respect the importance of continuous mosquito work becomes particularly apparent, because at times the results obtained seem almost to be of a contradictory nature; but these variations are due to the diverse conditions under which mosquitos are forced to live in a country which at one time is subject to excessive rains and at another in the throes of a great drought. These factors tend to give to certain mosquitos an economic significance, and therefore we must not be surprised to find a semi-domestic species like A. notoscriptus displaying at times a tendency to become domestic; this mosquito has already taken to breeding in water-tanks in Western Australia, and fears of its doing so in Brisbane, when its present breeding-places have been largely done away with, seem justified.

Definition of the genus Calliptamus (Orthoptera: Acrididae) has generated many taxonomic debates. Even now, the existence of different geographical morphs hinders species determination, particularly as concerns females and larvae. Some of these species are observed in southern France and are recognized as potential pests. To circumvent problems of species identification in ecological surveys, we developed a single multiplex PCR method based on mitochondrial Cytochrome Oxydase I diagnostic polymorphisms to differentiate between the four species, Calliptamus italicus, C. wattenwylianus, C. siciliae and C. barbarus, in southern regions of France.

Several published reports have presented estimates of the rate of increase, r, based on sampled ovarian age distributions from Glossina populations throughout Africa. These estimates are invalid, because an age distribution sampled at one point in time can be equated to a survivorship curve only if r = 0. When such a survivorship curve and a corresponding fecundity schedule are then used to estimate r via the Euler-Lotka equation, the result is a value of r near zero, regardless of the population's true rate of increase. Synthetic sampling from a hypothetical tsetse population confirmed that estimates computed in this fashion are entirely the products of sampling error. Valid estimates of r can sometimes be obtained from an age distribution, using an alternative method, but such estimates are highly sensitive to sampling errors in the distribution.

The Capsid bugs, Sahlbergella singularis, Hagl., S. theobroma, Dist., and Helopeltis bergrothi, Reut., have been recognised as pests of cacao in the Gold Coast for more than 30 years7,8. Whilst there has never been any divergence of opinion as to the major status of Sahlbergella as pests of cacao, this does not appear to be true of Helopeltis. Patterson (see various reports of the Gold Coast Department of Agriculture,17, 18, 19, 20) considered Helopeltis to be a major pest and indicated that damage to shoots, as well as to pods, is frequent; whereas Cotterell3 describes H. bergrothi as a minor pest of cacao and states that “damage to herbaceous shoots is of very rare occurrence.” In 1939 Cotterell6 reported that he had found another Capsid (? Bryocaropsis sp.) to be comparatively widespread on cacao around Tafo.

The following systematic work was carried out in the Entomological Department of the British Museum and is based on material in the National Collection. An endeavour has been made to extend the area of the field usually covered by the systematist in his search for characters, although the author ia well aware how far short of the ideal in this matter the paper falls. The species described are:—

The chalcidoid wasps of the genus Monacon develop as parasites of the larvae of ambrosia beetles (mainly Platypodidae) in the tropical forests of the Old World. Their known hosts are reviewed. A key is given to species, which are treated in two groups, according to geographical region: first the Indo-Australian species, then the African ones. The previously known Indo-Australian species come from India and Bangladesh (two), North Borneo (one) and the Philippines (one), and another 14 are here described as new: two from Sri Lanka, two from Burma, two from West Malaysia, one from both West Malaysia and the Philippines, two from the Philippines only, four from Papua New Guinea only and one from both Papua New Guinea and the Philippines. Three African species were previously known from Zaire; one of them has now been found also in Uganda. Three species are described as new: one from Uganda, one from both Uganda and Nigeria and one from Kenya.

The effects were examined of constant temperature on the life-cycle of Paulinia acuminata (Deg.), a potential biological control agent for Salvinia molesta. Over the range of temperatures tested (25–36°C), the duration of the life-cycle varied from approximately 85 days to 38 days. Egg development was most rapid at 33–36°C, but percentage hatch was greatest at 33–34°C. The duration of the nymphal period continued to decrease up to 36°C. The optimum temperature for nymphal development appeared to be higher than for eggs since temperature did not significantly affect nymphal mortality, which was about 50%. There were sometimes five and sometimes six instars, six being rather more common at lower than at higher temperatures. Crowded nymphs developed more slowly than isolated ones. Population growth rate statistics were calculated by combining data from several series of experiments. In an attempt to predict the results of a release of Paulinia at Lake Kariba between Zambia and Zimbabwe, these statistics were related to the mean annual temperature on the lake. It was estimated that P. acuminata would undergo three generations a year, with the population increasing by a factor of 8000 per annum.

Although Myzus cerasi is sometimes a serious pest of the cherry, and is therefore of economic importance in Great Britain, the life-history has never been completely worked out in the Eastern Hemisphere. A good deal of work has been done upon the species in America, and the life-history is recorded by W. A. Ross1 as it occurs on that continent.

Amongst 20 tea clones tested in Sri Lanka for susceptibility to Glyptotermes dilatatus (Bugnion & Popoff), five of the high-yielding soft-wooded clones, including the currently recommended and popular TRI 2023 and TRI 2026, were found very susceptible and to suffer a severe net loss in yield. A highly significant negative linear correlation was observed between the mean infestation percentage of clone with an infestation of over 30% and the mean percentage change in yield. In general, the high-yielding clones with soft-wooded sappy frames were particularly susceptible to termite attack. Since yield is one of the important criteria for selection, it is suggested that in areas prone to termite infestation, replanting should be limited to the high-yielding resistant clones such as GMT 9, KEN 16/3 and DG 39. The provision of shade with Gliricidia sepium may have prevented a steep increase in the incidence of infestation in the susceptible clones.

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

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

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

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

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

Confusion in ecological data previously published on Tyrophagus is thought to be attributable in part to similarities in the morphology, geographical distribution and ecology of its species, and to their close association.

During the course of work on coconut pests in the British Solomon Islands Protectorate, from August to October, 1928, I took the opportunity to make a collection of mosquitos. Ten weeks were spent in the country, but most of this time was occupied in travelling round the group on brief visits to many islands, and on only two occasions were more than three days spent in any one locality. It was not possible, therefore, to make anything like an exhaustive collection of the mosquito fauna.

Since the recognition by Bolivar (1912) of Hieroglyphus nigrorepletus as a distinct species, Coleman's (1914) note and Uvarov's (1922) valuable revision of the rice grasshoppers, it has been clear that in the earlier literature this species has been confused with H. banian, F., chiefly under the name of H. furcifer, Serv., while H. bettoni, Kirby, 1914, and H. vastator, Carl. 1916, are synonyms.

1. The main food hosts of Glossina swynnertoni in a district of Tanganyika appear to be (a) one or more Bovids, perhaps kudu or roan, exhibiting a close blood relationship to ox or buffalo ; (b) giraffe ; (c) pig. There is evidence that monkey or baboon is also made use of and that zebra definitely is not.

2. With regard to G. palpalis on Maboko Island, crocodile and hippopotamus are important hosts. But they are far less important than we had supposed. The majority of flies appear to have fed on some animal not yet determined.

In studies in Nigeria, survival and weight increase of the larvae of Cydia ptychora (Meyr.) were affected by the variety of cowpea (Vigna unguiculata) on which they fed. The weights of fifth-instar larvae immediately prior to pupation and the amount of fresh food ingested were similar on three varieties when loose seeds were fed, but in a more natural situation, larvae appeared to face a manoeuvrability problem in small pods, which resulted in reduced weight gain. Differences in weight due to diet were less pronounced in emerging adults. Larval mortality was greatest on two varieties with large pods and may have been related to the nutritional quality of mature seeds or the presence of toxic chemicals. Some first-instar larvae died during the pod-boring process, particularly in the variety Vita-5. Two known susceptible varieties produced a moderate-to-small degree of mortality and large females. Significantly greater weight was attained when larvae fed for five days on 10-day-old seed followed by 15-day-old seed, or on 15-day-old seed throughout, than on 15-day-old seed followed by dried seed, or on 10-day-old seed throughout. Ovipositing females seemingly select pods of an age that minimises exposure of young larvae to drying or fully dried seed, which is a relatively unsuitable diet.

Investigations on the Akah river, in the 4th Division of Sarawak, showed 13 species and one variety of Anopheles to be present. A. l. leucosphyrus Dön., the principal malaria vector, was the only species common in houses.

A. l. leucosphyrus has a strong preference for human blood and feeds throughout the night, with a peak of activity soon after midnight. Both fed and unfed mosquitos rest indoors on the walls but the latter become increasingly scarcer later in the night. Most individuals rest low down (62% below 3 ft., 96% below 5 ft.) but only a negligible percentage remains in the house after daybreak. Observations suggest that many females spend quite long periods resting outside the house before entering and that entry is almost entirely through windows and other openings in the walls; very few enter the space below the house. There is also evidence of two separate stimuli, or levels of activation, one bringing the mosquito to the bait and one initiating the act of feeding.

Wet weather was accompanied by an abrupt increase in catches of A. l. leucosphyrus and dry weather by a decrease—this is thought not to be due to any effect on breeding places. During the wet period, females entered earlier and tended to rest to a greater extent before feeding.

(1) There are two forms of D. superstitiosus, F., in Nigeria, which are designated banded and spotted forms in the present paper. The banded form appears on cotton earlier in the season than the spotted, and it remains on the crop longer. Migration to cotton is gradual in the case of the banded form, while a sudden influx of migrants of the spotted form commences in October. Many spotted adults migrate to Bombax and Sterculia between January and March, whereas the banded form remains on the cotton until it is uprooted at the end of March. The spotted form is far more numerous than the banded on maize and guinea corn.

(2) There is considerable variation in the colouration of adults of the spotted form; at Ibadan about 99 per cent. of the migrants to cotton are yellow or orange in colour, while the adults of the filial generations produced on cotton are almost always red in colour (a few individuals are deep orange-red). These colour variations are thought to be of seasonal origin.

(3) D. superstitiosus is the most prevalent species on cotton at Ibadan, Ilorin, Oyo, Zaria and Kano; melanoderes is of equal or greater importance in the forest zone at Ilugun and occasionally is numerous at Ibadan; fasciatus is of importance in savannah country at Oyo; haemorrhoidalis is rare on cotton. No evidence has been obtained that any one of these species is a varietal form of another species. Both forms of superstitiosus are widely distributed in Nigeria.

(4) Migration to cotton is induced by the flowering of that crop. The maximum weekly migration has occurred between the weeks ending 15th October and 7th November in five localities in the last three years; viz., at the time of, or soon after, the maximum flowering of the cotton crop. There are indications that there is a tendency for stainers to migrate in a southerly direction, probably as a result of the desiccating harmattan wind from the Sahara.

(5) The principal alternative food-plants of stainers in the Ibadan district are: Bombax sp., Sterculia sp., Hibiscus esculentus, H. sabdariffa, Urena lobata, and Abutilon zanzibaricum. At Ilorin, silk-cotton trees (Bombax), H. esculentus, H. lunariifolius and U. lobata are the most important alternative food-plants.

(6) A rhythm exists in the weekly proportions of the sexes during the cotton season; males predominate among the early migrants to cotton and among the first individuals to mature of each generation. This rhythm appears to be the result of shorter period of post-embryonic development in the case of males than in that of females derived from the same batch of ova.