In Queensland, adults of the soldier flies Inopus rubriceps (Macq.) and I. flavus (James) emerge between March and June, usually on still warm days. The females mate and oviposit on the day of emergence, the eggs being deposited close to the soil surface under small clods or in cracks. Incubation takes 6–13 days, depending on temperature. Observations on larvae reared on maize seedlings showed that the wide size range in field populations of larvae at all times of the year was due to the differing rates of development of larvae of one generation, to overlapping generations and to a difference in size between the sexes. One-third of the larvae matured to adults at the end of one year, but only a few of the remainder survived to emerge as adults after two years, one-year larvae having 8–9 instars, and two-year larvae having 10–12. Pupation occurred within the last larval skin, and the pupal period lasted three weeks.

Two strains of Blattella germanica (L.) were developed from a laboratory colony that was resistant to diazinon, propoxur, pyrethrins, lindane and DDT due to selection with diazinon. One strain was reared for nine generations without selection; the other strain was selected with propoxur for 14 generations; selection of the parent strain with diazinon was continued. Resistance to all five insecticides was stable for nine generations in the unselected strain, indicating fixation of the recessive genetic factor for diazinon and propoxur resistance and the incompletely dominant factor(s) for pyrethrins, lindane and DDT resistance. Diazinon and propoxur were equally effective as selecting agents for increasing resistance to diazinon, propoxur and pyrethrins and maintaining resistance to lindane and DDT. Resistance to diazinon and propoxur is probably due to a single recessive factor which attained genetic fixation by selection with diazinon. Cross-resistance to pyrethrins, lindane and DDT, also fixed by diazinon selection, is not due to heterotic effects but may be the pleiotropic action of the diazinon-resistance gene or due to a separate genetic system. The practical implications of this research are discussed.

The taxonomic status of the Chondrilla gall midge, Cystiphora schmidti (Rübsaamen), is discussed and new generic and specific synonymy is established in the genus Cystiphora. Male, female and larval characters of C. schmidti are described and illustrated on the basis of specimens made available from recent studies of this species in Europe as part of a project to implement biological control of Chondrilla juncea in Australia.

A history of the changes in nomenclature within the genus Spodoptera is outlined. A key to the imagines of the eight species occurring in Africa and the Near East is presented, together with keys to the larvae and pupae of most of these species, including all those of economic importance in this region, as well as brief notes for identifying the eggs of six species. For each species, a separate account is given of its taxonomic features and affinities, general world and more detailed African distribution, as well as host-plants, including those of economic importance, and its vernacular names. The subspecies Spodoptera leucophlebia malagasy Viette, recorded only from the Malagasy Republic, has been raised to full specific status, and should now be known as Spodoptera malagasy Viette, stat. n.

From field observations and laboratory rearings, the biology of Forcipomyia squamipennis I. & M. in cocoa plantations in Ghana was established as follows. Adult midges are found between buttresses of large shade trees, in crevices of decayed old logs, in hollow tree stumps and cocoa husk heaps. Swarming takes place at any time during the day in or around the resting place, while dispersal occurs in the early morning and in the late afternoon, the normal flight range being 5–6 m. The largest populations occur in the rainy season. Eggs are laid on moist decomposing wood, cocoa husks and other plant debris in batches of 40–90; the larvae hatch in 2–3 days and pupate after four moults, when about 12 days old; the pupal stage lasts 2–3 days. Adult females require liquid plant food for survival and oviposition, although the maturation of ova is independent of adult food intake or mating; unfertilised eggs do not develop. The maximum adult life span for both sexes is eight days in captivity. F. squamipennis undergoes at least 12 generations a year. Due to its abundance and continuous breeding in cocoa plantations, F. squamipennis is probably the most important Ceratopogonid cocoa pollinator in Ghana. Both sexes are efficient pollinators, but four times more males than females visit cocoa flowers.

Numerous habitats were sampled for larvae of sheep headfly, Hydrotaea irritans (Fall.), in infested areas of Northumberland during the winters 1973–74 and 1974–75. Most of the larvae found came from near the surface of soil beneath pasture and long grass. The mean larval density in these sites was 1·93/m2; the greatest density in a single site was 3·87/m2 which compares well with unpublished estimates of adult fly density. Only two larvae were recovered from cow dung. One larva was found in bracken litter, and none in other types of litter, or in horse dung, peat, moss or rotten wood. Larvae were reared to the mid-third instar from eggs laid in the laboratory. Field-collected larvae fed readily on Musca and Calliphora larvae, and did not appear to diapause in December; their identity was confirmed by rearing them to the adult stage. The egg, second- and third-instar larvae, and puparium are described and figured. Descriptions are given of changes in the mouthparts during growth of the third-instar larva, and of the features by which field-collected larvae can be identified.

A Cecidomyiid gall midge, Cystiphora schmidti (Rübsaamen), lives on several related Chondrilla spp. occurring from Greece and eastern Europe to Iran. Its biology and host specificity were studied in the eastern Mediterranean region as part of the biological control programme against the weed C. juncea (Compositae, Cichoriaceae) in Australia. The adult female oviposits into the lower epidermis of the plant where small circular to ovoid raised galls are produced on the rosette, stem leaves and the stem. All the immature stages are completed inside the gall in 24–44 days, allowing 6–7 generations per year in southern Greece before low temperatures prevent development of overwintering larvae. The midge is heavily parasitised in Greece by two species of Eulophidae. Particularly in southern Greece, dense gall populations cover the leaves and stems of C. juncea, causing death of leaves, stunting and less seeding. Tests against 76 species of plants including some Cichoriaceae closely related to Chondrilla showed that Cystiphora schmidti is specific to the genus Chondrilla. Comparative tests with Cystiphora schmidti from Greece against four forms of Chondrilla juncea showed that the midge was adapted to its usual Greek host but was less closely adapted to a western Mediterranean form. The Greek strain of the midge readily attacked and thrived on the main Australian form of C. juncea.

The larvae of ten species of Ixodid ticks are described, particular emphasis being placed on the setation of the capitulum and palps, and a key is provided to the larvae of 14 species from the eastern Cape Province of South Africa that are common, economically important or difficult to separate. Important characters are illustrated in 62 scanning electron micrographs.

The vertical distribution of mosquitoes was investigated at Keneba in The Gambia, using flight traps and suction traps set up over open ground. Flight traps were used to sample three levels, ground to 1·37 m, 1·45–2·82 m, and 2·90–4·27 m. Suction traps were mounted in two series of experiments at three levels, 0·68, 2·13 and 3·51 m, and in a third series at four levels, 0·91, 305, 6·10 and 9·15 m. Most species, including Anopheles melas Theo., A. squamosus Theo., Aedes punctothoracis (Theo.), the Culex decens group, C. tritaeniorhynchus Giles, Mansonia africana (Theo.) and M. uniformis (Theo.), were most common near the ground, with catches declining progressively with height. C. thalassius Theo. was frequent at all levels, although the largest catches were taken at 9·15 m. Only C. neavei Theo. and C. weschei Edw. were more common in the higher traps. Although larger catches of A. melas and C. tritaeniorhynchus were taken during moonless periods, the numbers of other species were unaffected by lunar phase. In general, the presence or absence of moonlight had little effect on vertical distribution. However, C. thalassius and the C. decens group were shown to be more attracted to flight traps in moonlight, and it is concluded that visual responses were involved. A limited series of four-level, human-bait catches, with the catchers stationed at the same heights as the suction traps of the third series, produced results similar to those of the suction trap collections.

Hungry tsetse flies (Glossina morsitans Westw.) are confined individually on the stretched wing membrane of a bat. Only 10–20 s after the tarsi touch the membrane, the flies probe and salivate, the main saliva flow following after penetration. The clear colourless saliva is easily collected onto a microscope slide.

The biology and population fluctuations of the non-biting Muscid Hydrotaea irritans (Fall.) were studied in two contrasting areas of Surrey using a standardised catching technique at selected sites, by analysing catches and by dissecting the collected flies. Following the first appearance of adults in early June, catches reached a maximum in late July, the males having fallen to a small proportion by early July. During August catches gradually fell, remaining at a relatively low level for the rest of the summer. The complete life-cycle, starting with eggs from caged fly colonies, took 295 days under sheltered outdoor conditions. The fly is univoltine, with three larval instars; larvae leave the egg in the second instar which is a brief, saprophagous stage, while the third, principal stage is predatory on other insect larvae. Overwintering normally occurs as a late-stage larva. Flies collected from sheep-grazing areas in Northumberland were shown, using serological methods, to have fed predominantly on cattle blood protein.

Descriptions are given of the nymphs of five species of ticks from the eastern Cape Province of South Africa, namely Amblyomma marmoreum Koch, A. nuttalli Dönitz, Hyalomma marginatum rufipes Koch, Rhipicephalus evertsi Neumann and Ixodes pilosus Koch. Distinguishing characters are illustrated in 32 scanning electron micrographs.

The amino acids of the haemolymph proteins of female Glossina austeni Newst. have been analysed at selected times during the first two pregnancy cycles by automatic amino acid analysis. The most prominent amino acids were glutamate, aspartate, lysine and leucine, with these amino acids accounting for almost 50% of the total amino acid residues. The molar percentage of all 16 amino acids observed varied only slightly throughout the pregnancy cycles. The amino acids of the perchloric acid-precipitable fraction of the gut contents of third-instar larvae (considered to be equivalent to milk secretion) have also been analysed and differ considerably from the haemolymph proteins, with glutamate and phenylalanine particularly prominent. Because of their low content of aromatic amino acids, the haemolymph proteins are not regarded as an important store of these compounds.

The male of the predominant cave-dwelling Phlebotomine in Belize (formerly British Honduras) is described under the informal name of Lutzomyia beltrani (Belize form). Differences between this fly, L. beltrani (Vargas & Díaz Nájera) and L. steatopyga (Fairchild & Hertig) are discussed. The females of L. beltrani, L. steatopyga and L. beltrani (Belize form) are indistinguishable.

A total of 167 blood-fed mosquitoes of the genera Ficalbia, Mimomyia and Uranotaenia was collected from the Kisumu area of Kenya using Monks Wood light-traps under the outside eaves of houses, CDC light-traps inside houses and sweep-net catches. Precipitin tests were used to obtain 72 positive identifications of the hosts, 89% of which were amphibia. M. mediolineata (Theo.) and M. splendens Theo. were shown to feed occasionally on man while U. balfouri Theo. and M. hispida (Theo.) were shown to feed on other mammals, including cattle. No identification was effected from a single F. uniformis (Theo.) specimen collected resting in vegetation. The medical importance of these mosquitoes is uncertain but, since there is evidence for several arboviruses in amphibia, further study of these potential vectors should be undertaken.

Pomello and lemon seedlings kept for different time periods in various nutrient solutions were examined for their degree of infestation with Aceria sheldoni (Ewing), the citrus bud mite. Chemical analyses indicated that seedling leaves and buds had a higher nitrogen content in a potassium-free solution, and a lower nitrogen content in a nitrogen-free solution, when compared with their respective contents in a standard solution; in buds these differences were also shown by certain amino acids. Infested seedlings kept in a potassium-free solution had significantly more mites than those kept in a nitrogen-free solution, and the latter had significantly fewer mites than those kept in a standard solution. No increase in mite populations was noted on seedlings kept in high-nitrogen solutions. The relationship between the levels of potassium, nitrogen, magnesium and manganese and the mite population is discussed. No effect on mite reproduction was noted when sodium or calcium was used as a substitute for potassium.

Between 1963 and 1969, approximately 15 000 Phlebotomine sandflies were collected in five limestone caves in Belize, Central America. Thirteen species of sandflies were identified, two of the genus Brumptomyia França & Parrot and 11 of the genus Lutzomyia França. L. beltrani (Vargas & Díaz Nájera) was the predominant species in all the caves; it is wholly adapted for life in caves and data on blood-meals and ovarian development allow a detailed discussion of its probable life-history (four generations per year) in relation to its supposed hosts, bats. Some specimens of L. deleoni (Fairchild & Hertig) were collected in all caves and it was the second most abundant species in all but one cave; this species, whose larval stages develop in the caves, is evolving from life in caves and is becoming adapted to life in forest. L. trinidadensis (Newst.) was abundant in one cave but rare in the others; this species probably enters caves in search of hosts for blood-meals. The eight other species of Lutzomyia and the two species of Brumptomyia were collected in small numbers and at irregular intervals; these species use caves only as temporary shelters.

The trend in the relative populations of Oryctes rhinoceros (L.) in two areas of the Gazelle Peninsula, New Britain, was studied by trapping adults searching for breeding sites. In a high rainfall area with 10-year-old palms and many possible breeding sites, there was a large initial population of beetles which declined over the next three years with the gradual disappearance of the breeding sites; weekly catches were higher when the undergrowth in the trapping area was slashed, and to some extent also at new moon; catches were depressed by heavy rain. The ♂/♂ sex ratio was 0·31; all females had mated and had mature eggs in the lower ends of the oviducts. These results were compared with those from a low rainfall area with 70-year-old palms and dispersed breeding sites. Catches were generally lower; they showed no long term trend and were not related to slashing or weekly rainfall, but were inversely related to the number of rainy days per week.

Aedes (Ochlerotatus) fryeri (Theo.) was found developing in saline pools on the coastal margins of coral islands near Dar es Salaam, Tanzania. Females were autogenous in the first ovarian cycle and anautogenous in the second ovarian cycle. The existence of autogeny was confirmed by examination of females reared from field-collected pupae and of the age structure of the population of females landing and biting. All females receiving carbohydrate and most females receiving only water as adults exhibited autogeny; only parous females were caught attempting to take blood. Water-fed females (and to a lesser extent, carbohydrate-fed females) showed a high incidence of follicular regression in the first gonotrophic cycle. The possible adaptive significance of autogeny in A. fryeri is briefly discussed.

Laboratory colonies of Monomorium pharaonis (L.) were given access only to food containing the juvenile hormone analogue isopropyl-11-methoxy-3, 7, 11-trimethyl-dodeca-2, 4-dienoate (Altosid). In contrast to control colonies all the brood died in 4–8 weeks and queens ceased to lay eggs at about this time. Comparison of ovaries dissected from treated and untreated queens showed the former to be atrophied and without developing oocytes. In treated colonies the worker caste became extinct between 9 and 20 weeks after treatment commenced but queens remained alive for more than 20 weeks. Treatments were lethal with exposure periods of one week only. Juvenile hormone analogues show real potential for the control of M. pharaonis.