In a field study in eastern Tanzania, the behaviour of 4167 males and females of Glossina morsitans morsitans Westw. from a colony fed on equine blood through artificial membranes (Seibersdorf flies) was compared to that of 4065 flies from a colony fed on goats or rabbits (Tanga flies). All flies had been treated with 11·8 krad γ-irradiation, a sterilising does, in the late puparial stage in a saturated nitrogen atmosphere. Recapture rates were 5·66% for Seibersdorf and 4·50% for Tanga flies. Only 57% as many Tanga females were recaptured as compared to Seibersdorf females, but the Tanga females had a higher insemination rate. The age-distribution and dispersal of the recaptured flies of the males of both groups and of the females were similar. Laboratory studies showed that although there were no marked differences in fat reserves between males of the Tanga and the Seibersdorf strains, the Seibersdorf females had significantly more fat than the Tanga females.

Temelucha minuta (Morl.), a common parasite of Phthorimaea operculella (Zell.), is redescribed with emphasis on features enabling it to be separated from other species of Temelucha. T. clausa Kerrich is placed as a junior synonym of T. minuta. The known geographical range of the parasite is expanded to include Cyprus, Australia and India. A provisional key is given to the Australian species of Temelucha, and notes are given on their distribution and hosts. T. verimaculata (Cam.) is placed as a junior synonym of T. australiensis (Szépl.).

In studies in the Zambesi Valley, Zimbabwe, carbon dioxide alone dispensed at 2·5 to 15 litres/min, or acetone alone dispensed at 0·3 to 300 g·h, increased by up to six times the catches of Glossina morsitans morsitans Westw, and G. pallidipes Aust. from stationary biconical traps, stationary electrocuting traps used with and without a visual target, and a mobile party of hand-net catchers. Catches were increased further when the chemicals were dispensed together. Carbon dioxide at 2·5 litres/min plus acetone at 15 g/h was about half as effective as ox odour for enhancing the catches from an electrocuting trap plus target; the efficacy of carbon dioxide at 15 litres/min plus acetone at 300 g/h was not significantly different from that of ox odour. Several short-chain ketones, and also formaldehyde and propionaldehyde, were attractive. Several long-chain ketones, and also heptaldehyde and caproic acid, were repellent. Carbon dioxide was attractive for Tabanidae, Stomoxyinae and non-biting Muscidae. Acetic acid was repellent for Stomoxyinae and non-biting Muscidae.

Specimens of a leafhopper from Jamaica, previously thought to be Osbornellus bimarginatus (DeLong) and which is suspected of being the vector of lethal yellowing disease of coconut, were found to belong to a new species. This is described as O. dabeki sp.n. and compared with related species. Genitalia of the male of Caribovia intensa (Wlk.), hitherto unknown, is described, and this species is compared with and shown to be distinct from C. coffeacola (Doz.).

Catches of Glossina morsitans morsitans Westw. and G. pallidipes Aust. were made on electric nets baited with the odour of one ox, in deciduous and riverine woodland in the Zambesi Valley of Zimbabwe. Catches of teneral and mature flies of both sexes and species declined sharply during the hot dry season (September to November) in the deciduous woodland. In the riverine woodland, catches of mature G. m. morsitans increased during this period; catches of mature G. pallidipes rose rapidly to a high level in June (early in the cool dry season), which was maintained for most of the dry season. Catches of teneral flies in the riverine woodland were fairly constant from June to September (the cool dry season and start of the hot dry season) and then declined, though not as sharply as in the deciduous woodland. The percentage of tenerals in the catch showed a minimum at the end of the hot dry season (October–November); at that time there was also a dramatic rise in the female: male ratio in the deciduous woodland, but no such change occurred in the riverine area.

Known components of the female sex pheromone of Spodoptera littoralis (Boisd.), tetradecyl acetate (I), (Z)-9-tetradecenyl acetate (IIA), (Z,E)-9, 11-tetradecadienyl acetate (III) and (Z,E)-9, 12-tetradecadienyl acetate (IV), and related compounds dispensed from polyethylene vials were used to bait water traps and funnel traps in lucerne fields in Crete. In comparison with the catches of males in traps baited with the primary component (III) alone, catches were increased by the addition of 1–100% of I in relation to the amounts of III, decreased by the addition of 5% or more of IIA and decreased by the addition of more than 5% of IV. The diene III was more attractive than any of the other three geometric isomers, although combining the Z,Z isomer (V) or the E,E isomer (VI) with III increased catches while the addition of the E,Z isomer (VII) decreased catches. The alcohols VIII and IX corresponding to the acetates III and IIA were not attractive but caused a marked reduction in trap catch when combined with III. The homologue of III (Z,E)-11-methyl–9, 11-tetradecadienyl acetate (X), was unattractive to males but increased trap catches when combined with III. 9-Tetradecynyl acetate (XI) exhibited neither attractant nor inhibitory activity, and similar results were obtained with ethyl cyclohexane carboxylate (XII) and 2-nonynal dimethyl acetal (XIII), compounds which have similar far-infrared spectra to that of diene III. The distributions of males landing on sticky board traps 70 cm in diameter baited with III or mixtures of III with I, IIA or IV showed that a greater percentage of the moths landed at the periphery of the traps baited with certain combinations of III with I and IV than on traps baited with III alone. Collection and analysis of the volatiles emitted by virgin females of different origins indicated that those from Crete produced I and III only, those from Israel produced I, III and IV, while those from Egypt produced I, III, IV and IIA and/or (E)-11-tetradecenyl acetate (IIB). The results are discussed in relation to previous work on S. littoralis and current theories on insect communication, and also in terms of their relevance to the practical field usage of pheromones in control of this pest.

The number of tsetse visiting a black cylindrical model (designed to look like a small host animal) in the Zambesi Valley, Zimbabwe, was estimated by catching them on an expanse of electric netting placed next to the model. The number which alighted was found by electrocuting the flies on the surface of the model on other occasions when the netting was absent. About half the Glossina morsitans morsitans Westw. visiting a stationary small model (a black drum 57 cm long and 37 cm in diametter) in the absence of ox odour alighted on it, but virtually none of the G. pallidipes Aust. alighted. When the linear dimensions of the standard model were increased threefold, about 1·5 times as many tsetse visited its close vicinity. Of these, nearly all the G. morsitans and about one-third of the G. pallidipes alighted on the model. Four to seven times as many tsetse visited the models when the odour of one ox was dispensed near them. When odour was present, about 1·5 times as many tsetse visited the large model as visited the small one. Some 55–85% of G. morsitans visiting the small model in the presence of ox odour alighted, but only about 30% of the male and 20% of the female G. pallidipes alighted. The latter percentages increased to 53 and 62 when the large model was used. A smaller percentage of G. morsitans females landed on the large model in the presence of ox odour than in its absence. With mobile models, significantly more tsetse were taken if electric nets were appended fore and aft of the model. In the absence of electric nets, 2–30 times as many tsetse landed on the large model as on the small one, the effect being greater for female G. morsitans than for males and much greater for G. pallidipes than for G. morsitans. The percentage of visiting flies of both sexes and species that landed was greater when the large model was used.

The mating behaviour of females of Glossina pallidipes Aust. from Kibwezi Forest, Kenya, was investigated in the field and in the laboratory. Field studies showed that very few tenerals were inseminated, that most nulliparous females become inseminated after the first blood-meal and that of females caught on a moving vehicle the majority of recently fed nulliparae were not inseminated while most non-teneral nulliparae with little or no residual blood-meal were inseminated. This suggested a mate-seeking behaviour by uninseminated, non-teneral nulliparae. Field data indicated that multiple insemination occurs in some nulliparae. In the laboratory, few females were receptive until 4–5 days old, which conforms to the field data. Peak receptivity in virgins was reached about nine days after eclosion, when more than 90% copulated. Receptivity in virgins decreased from about two weeks after eclosion. Females permitted one copulation a day between days 0 and 13 copulated, on average, 1·4 times; 38% copulated twice and 2% three times. Receptivity in virgins was higher than in non-virgins, suggesting that one or more components of the copulation affect receptivity.

The efficiencies of five mechanical traps and an electric trap for tsetse flies were measured by estimating the numbers of flies which approached the devices but were not captured by them. With this method, it was possible to discern significant differences in efficiencies even if the means differed by as little as 25%. Three biconical traps had estimated efficiencies of 40–70% for Glossina morsitans morsitans Westw. and 50–80% for G. pallidipes Aust. when used in the presence of the odour of one ox. The efficiency of a small electric net was estimated at 70–75% for all tsetse under this test condition, and a modification of one of the biconical traps had an estimated efficiency of 55–85%. The efficiency of this trap increased by a factor of 1·2–2·2 when used with the odour of six oxen, compared to the efficiency in the absence of host odour. Preliminary results suggested that, when used in the presence of ox odour, the efficiency of this trap for teneral tsetse was at least as high as for mature flies.

The identity of Lecanium krugeri Zhnt. is established, and the species is redescribed in a new genus Saccharolecanium. Originally known from Java, the species is now recorded from India and West Malaysia on sugar-cane.

The genus Sosylus includes important natural predators and parasites of ambrosia beetles (Platypodidae). Nine species of Sosylus are recorded from New Guinea (Papua New Guinea and Irian Jaya in Indonesia), and a key is provided for their identification. Five of the species, S. giluwe sp. n., S. hyweli sp. n., S. minusculus sp. n., S. morobensis sp. n. and S. reflexus sp. n., are described as new and one, S. erosus (Pasc.), is recognised as an extension to the known range of an existing species. New information is presented concerning the distribution and sexual dimorphism of the previously described species, and lectotypes are designated where necessary and feasible.

A gracillariid moth belonging to the subfamily Lithocolletinae that was reared from larvae mining the leaves of Lonicera quinquelocularis (Caprifoliaceae), a weed in northern Pakistan, is described and named Phyllonorycter montanella sp. n. The larvae make blotch mines on the underside of the leaves and were discovered in the Murree Hills at about 2600 m.

Adults of Cnaphalocrocis medinalis (Gn.), a widely distributed pest of rice, were found to require an exogenous source of sugar, life-span and fecundity being greatly increased in the laboratory when sugar was available. Their sources of sugar in the field are not known, but evidence is presented which shows that in the laboratory they can utilise the honeydew produced by Nilaparvata lugens (Stål), a common pest of rice.

A description is given of some of the developmental stages of Sosylus vicinus (Grouv.), S. silius Hinton and S. reflexus Pope from Papua New Guinea. At least three instars are recognised in all species, and the first or primary instar is of the triungulin type. A triungulin is also reported as the primary instar of another colydiid, Asosylus rhysodoides (Pasc.). This is the first time triungulins have been found in the coleopterous family Colydiidae. Differences in the triungulin of the three species of Sosylus are recognised, based on the form and arrangement of segmental spines. The structure of the different instars with regard to their habits on the host is discussed, and a brief comparison is made with larvae of Meloidae and Rhipiphoridae, the only two other families of Coleoptera with triungulin first-instar larvae.

In tests in Nigeria with its principal host-plant, cowpea, Cydia ptychora (Meyr.) showed distinct oviposition preferences. Most of the eggs were laid on the sepals (including their remains on pods) in screenhouse tests involving four varieties. There were distinct differences in the number of eggs laid on different varieties in both no-choice tests with four or five varieties and free-choice tests with 17 varieties in the field. Vita-3 was the preferred variety in the laboratory tests and H 13–1 in the larger comparisons in the field. Fewest eggs were deposited on Tvu 2994 in all tests.

The duration of flight by Nilaparvata lugens (Stål) of tropical origin from field and laboratory populations was studied. Field insects (from the third generation on rice) flew longer and more readily than laboratorybred insects. The longest recorded flight, of 10·75 h, was by a female from the field. Laboratory-reared insects performed poorly even after only one generation in the laboratory. Flights that were started in the morning lasted longer than those started in the afternoon. Lift production varied between individuals and during a continuous flight. Individuals flying for over 150 min tended to produce more lift for a longer proportion of the flight than those flying for less than 10 min. The pattern of lift production appeared to be similar in successive flights, except in those following very long flights when the insect appeared to be exhausted. There was no tendency for the first flight to be the longest. Up to 28% loss of body weight was recorded (in a flight lasting 512 min) during flight. The results indicate that individuals from tropical field populations of N. lugens have the capacity for long range migration.

The liquid excrement of many Homoptera, which often accumulates as honeydew, can be harmful to the insects that produce it. Disposal of excrement to avoid or reduce its harmful effect is therefore important. The methods of disposing of excrement in Coccidae are described. These insects have an anal apparatus for propulsion of excrement away from the body. The musculature of the rectum is not involved in this act. Attendance by ants modifies excretory behaviour in Coccidae, much as it does in Aphididae.

Counts were made of the numbers of Oscinella adults caught in water traps in plots of grass and oats and in a suction trap in north-eastern England in 1969 and 1970. The numbers of eggs laid by O. frit (L.), O. vastator (Curt.), O. nitidissima (Mg.), O. hortensis Collin and O. maura (Fall.) on their respective host-plants were also counted. In both years, there were two generations of O. nitidissima and O. nigerrima (Macq.) and one of O. maura. In 1969, there were two generations of O. frit and one of O. hortensis and O. vastator. In 1970, there were partial second generations of O. hortensis and O. vastator and a partial third generation of O. frit. O. nigerrima was the first species to appear in the spring, followed by O. frit and O. nitidissima. O. hortensis, O. vastator and O. maura emerged later, and these species dominated the trap catches in July. The proportions of O. frit and O. nitidissima increased in August, and by late September these species again dominated the catch. The proportions of O. vastator and O. hortensis in the suction-trap catches were much lower than in the water-trap catches. Adults of all species were always found in the grassland water traps before they were found in the suction trap. The migratory requirements of other species in the genus, in particular O. maura and O. vastator, may be less than those of O. frit. The oviposition period on particular grass species was relatively long, and thus control of Oscinella spp. on grassland would be difficult.

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.

Oryctes rhinoceros (L.) is a major pest of coconut palms in Papua New Guinea but has a limited distribution within the country. Pre-release monitoring showed that no baculovirus disease was present in the country prior to its importation. A consignment of O. rhinoceros larvae infected with a baculovirus disease was imported into Papua New Guinea from Western Samoa in 1977. The virus proved highly infectious to both larvae and adults of the local population of O. rhinoceros. During 1978 and 1979, adults were perorally infected with the baculovirus and released at nine sites on Manus Island, four sites on New Ireland and twelve sites on the Gazelle Peninsula of East New Britain. The infected adults were active disseminators of the virus into the field population, and the virus became established at nearly all the release sites. The shortest time between virus release and recapture of newly infected adults from a release site was eight weeks. Three different examples indicated the virus spread at approximately 1 km/month. During a fourteen-week period in the early establishment phase, significantly more females than males were collected in traps but a significantly higher percentage of the males was infected.