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.

Light-trap catches of Dysdercus bimaculatus Stål and weekly phenological records of its host-plants over a period of three years on Barro Colorado Island, Panama, are discussed in relation to a year-long study of population growth at selected plants. Population build-up of D. bimaculatus occurred on a sequence of seed crops from wild host-plants in the dry season. Each year, the largest number of bugs caught in the light-trap occurred after a drop in vapour pressure deficit marked the end of the dry season. Thus, the population appears ‘poised’ to attack cotton crops maturing in the late wet season. A stepwise linear regression indicated that each year, the variance in size of Pseudobombax septinatum crops (maturing at the end of the dry season) explained the largest proportion of variance in the light-trap capture of D. bimaculatus. However, estimates from the field study indicated that Ceiba pentandra crops were more important than P. septinatum in building up numbers of adult cotton stainers. The discrepancy between the field study and the longterm phonological monitoring survey would be resolved if D. bimaculatus adults experience a dispersal flight at the end of the dry season. This flight would enable the insect to locate better-quality seed crops in drier habitats that mature in the late wet season, such as Sterculia apetala or cotton. Light-trap captures at the end of the dry season in areas such as Barro Colorado Island where Ceiba and Pseudobombax occur, could be an index to the intensity of attack on cotton crops in nearby drier areas.

The family of the Trypetidæ is of great economic importance, for among its numerous genera are to be found many pests of the orchard and farm. The flies of this family are rarely brought to the notice of Europeans in West Africa, for there farming operations are entirely in the hands of the native population and the amount of damage done by these insects is perhaps insufficiently appreciated by Europeans; but from observations made in my own gardens, during a long West African experience, I believe the loss caused by their attacks must be considerable. The flies which are responsible for the damage observed belong to two genera—Ceratitis, MacLeay, and Dacus, Fabricius.

The adults of the weevil, Euthyrrhinus meditabundus, Fabr., were frequently taken in the forest country to the south of Darwin, Northern Territory, and on several occasions they were bred from the branches of two species of indigenous trees and from custard apples, Poincianas and two unidentified species of introduced ornamental trees growing in the Darwin Botanic Gardens. As a rule the infestation of these trees was not heavy, although Poincianas occasionally showed considerable injury. Mango trees, which were frequently badly damaged and sometimes destroyed by termites (Mastotermes darwinensis), appeared to be immune from attack by Euthyrrhinus, even when growing in close proximity to infested trees of other kinds.

This Anopheline was first found in Syria in the larval stage on 30th August 1941. Up to the time of writing, 11th October 1941, adults and larvae have been taken on several occasions. Isolated larvae have been bred to the adult stage, and larval and pupal pelts preserved. Through the courtesy of Professor S. Adler and Dr. O. Theodor, of the Hebrew University at Jerusalem, I was able to consult the literature regarding the distribution of this species and to confirm its identification. The discovery of Anopheles marten in Syria is a new record.

Au mois de mars de l'année 1933 j'ai accepté l'invitation de Monsieur E. Guest, Officier inspecteur de l'Agriculture en Iraq et en même temps Botaniste, de visiter l'Iraq pour lui aider dans quelques travaux qu'il voulait poursuivre, et le 30 mars j'ai quitté Jérusalem, accompagné par Monsieur Guest et par Monsieur M. Zohary, mon assistantet collaborateur. Arrivant à Baghdad les premiers jours d'avril, j'ai été invité par Monsieur le Ministre des Economies et des Communications et par le Directeur Général de l'Agriculture de faire cette visite au compte du Gouvernement Iraquien et de m'intéresser pendant mon tour spécialement aux problèmes de la botanique appliquée et particulièrement au problème des sauterelles et du reboisement et de l'afforestation. J'ai accepté volontiers cette invitation. Il me fallait prolonger le séjour en Iraq de dix jours de plus qu'il a été projeté d'abord. Ces dix jours étaient presque entièrement consacrés à l'étude de la végétation des champs de ponte des sauterelles.

In a recent number of this Bulletin, Lloyd and Johnson (1) attempted to describe and illustrate all the known types of flagellate infections encountered in Glossina. Since this account was written a flagellate, which it is believed has not previously been described, has been encountered in three individuals of G. morsitans at Sherifuri, Northern Nigeria. In the first two cases the worker at the microscope was new to the infections of tsetse and did not notice anything peculiar about the parasite in the proboscides that were being examined. The appearance of the parasites in the stained film caused one slide to be retained with a note, but it was at that time regarded as an aberrant T. vivax infection. In the second instance T. vivax was present, and the unusual forms accompanying it were remarked upon, but unfortunately the slide was not retained. In the third instance it was noticed in the fresh preparation that none of the parasites were fixed to the labrum, as are the vast majority of those in T. vivax infections, nor were they clumped as in this species and in T. congolense. Each individual was free-swimming and many were escaping from the labial cavity, the power of translatory movement being great. The hypo-pharynx was not invaded. The remainder of the fly was then examined and the mid gut was found to be heavily infected, while the salivary glands were negative.

Lablab purpureus subsp. bengalensis (Jacq.) Verdc. is an important legume of India and Africa. Both aphids, Aphis craccivora Koch and A. gossypii Glover (Hemiptera: Aphididae), are important herbivorous pests of this legume crop. These viviparous females lay nymphs on the leaf surface of this legume plant. Therefore, it is of considerable interest to study whether leaf surface wax chemicals (long-chain alkanes and free fatty acids) of this legume plant served as short-range attractants and oviposition stimulants in both females to lay nymphs. Twenty-one n-alkanes from n-C12 to n-C35 and 11 free fatty acids from C12:0 to C22:0 were identified in leaf surface waxes. Nonacosane and nonadecanoic acid were the most abundant among n-alkanes and free fatty acids, respectively. Both females were attracted towards one leaf equivalent surface wax against the control solvent (petroleum ether) in short Y-tube olfactometer bioassays. A synthetic blend of tetradecane, pentadecane, tetracosane, tridecanoic acid, tetradecanoic acid, and heneicosanoic acid comparable to one leaf equivalent surface wax served as short-range attractants and oviposition stimulants in A. craccivora; whereas a synthetic blend of tetradecane, hexadecane, docosane, nonadecanoic acid, and arachidic acid comparable to one leaf equivalent surface wax acted as short-range attractants and oviposition stimulants in A. gossypii. These results can provide the basis for efficient pest management strategies of A. craccivora and A. gossypii against L. purpureus subsp. bengalensis using host plant leaf surface wax compounds. Further, SEM studies of antennae and forelegs of both aphids were conducted to observe sensilla structures, which help in chemoreception.

Mutualism between ants and honeydew-producing hemipterans is a highly successful evolutionary innovation that attains the status of ecological keystone across many terrestrial ecosystems, involving a multitude of actors through direct or cascading effects. In these relationships, ants often protect their hemipteran partners against their arthropod natural enemies, sometimes interfering with the biological control of pest species. However, the dynamics of these interactions are highly variable based on the specific identity of all the actors involved, and baseline data remain scarce. We performed a field experiment exposing colonies of the walnut aphid Panaphis juglandis attended by five European ant species (Camponotus piceus, Ca. vagus, Crematogaster scutellaris, Dolichoderus quadripunctatus, Lasius emarginatus) to a native and an exotic lady beetle (Adalia bipunctata and Harmonia axyridis), documenting the behavioural interactions between these insects and the performance of ants in the protection of the aphids. Our results reveal a significant behavioural diversity among the ant species involved, with D. quadripunctatus and L. emarginatus being the most aggressive and having the best performance as aphid defenders, and Ca. piceus being least effective and often fleeing away. Cr. scutellaris displayed a rare rescue behaviour attempting to pull away the aphids that the lady beetles grabbed. On the other hand, behavioural responses to A. bipunctata and H. axyridis were similar. Further investigations are needed to understand the eco-ethological implications of these differences, while a better understanding of ant behavioural diversity may help refine biological control strategies.

The egg parasitoid Cleruchoides noackae Lin & Huber, 2007 (Hymenoptera: Mymaridae) is originated from Australia and the main biological control agent of Thaumastocoris peregrinus Carpenter & Dellapé, 2006 (Hemiptera: Thaumastocoridae) on Eucalyptus L'Hér (Myrtaceae). Companies that grow Eucalyptus are in need of a mass rearing protocol to increase the number of individuals produced and improve the quality of this parasitoid. The aim of this study was to define a protocol for mass rearing C. noackae in T. peregrinus eggs, based in the evaluations of the key biological attributes of this parasitoid in the parental and F1 generations, after the cold storage of the parasitised host eggs. Two methods were tested as C. noackae rearing protocols. In the first, parasitised eggs of T. peregrinus by C. noackae were cold stored for 7 days after being left in a climatic chamber at 24 ± 2°C, 60 ± 10% RH and a photoperiod of 12:12 (light:dark) h (standard environmental conditions) for 3, 6, 9 or 12 days. In the second, T. peregrinus eggs parasitised by C. noackae were maintained in a climatic chamber under standard environmental conditions for 6 days, after which these eggs were cold-stored for 0 (control), 7, 14 or 21 days. Parasitism (%), and the development period (parasitism to adult) and female proportion (%) of C. noackae were evaluated. Based on the results (parental generation: parasitism, around 45%; F1 generation: parasitism, around 55%; development period, around 16 days; female proportion, around 60%), eggs should be stored at 5°C on the sixth day after parasitism by C. noackae and maintained at this temperature for 7 days. The cold storage of T. peregrinus eggs, after parasitism, can be included in the mass rearing protocols of the parasitoid C. noackae.

Head black with pale scales; palpi black; proboscis black. Thorax and scutellum purplish brown. Abdomen black, with curved apical bands on the second, third, fourth and fifth segments and with lateral apical spots on the fifth, sixth and seventh segments. Legs black, unbanded.

Abgrallaspis pictor is described as new from specimens collected on Cymbidium sp.in a nursery in England. It damages the plants by causing leaf-spotting. The orchid plants were collected in North India in 1968.

Contarinia coffeae sp.n. is described from specimens reared from Coffea arabica in Uganda, and brief notes are given on symptoms, biology, crop loss and distribution. The larvae develop inside young coffee berries. Blister-like external swellings appear on infested berries and they later rot. The pest is known only from arabica coffee in parts of Western Uganda but may be spreading and could appear in other East and Central African countries.

A simple, but reliable, technique is described for the study of the acceptability to locust hoppers of poison baits under field conditions.

This was applied to the study of a number of vegetable materials which might be used for the manufacture of wet baits to destroy hoppers of the Desert Locust.

The materials tested could be divided into five classes of acceptability, and consideration of these indicated that heavy lignification detracted from acceptability while the presence of starch added to it.

It was shown that molasses adds to the acceptability of only the least acceptable materials unless very large amounts are used.

Simple tests showed that acceptability was not correlated with water-absorbing properties, that the rate of drying of bait was dependent on the amount of water initially absorbed, and that molasses influences the rate of drying only when large amounts are added.

Food-baited dishes were used to monitor the impact of ground-sprayed DDT (4% WP @ approx. 200 g/ha) and deltamethrin (0.05% SC @ 2.6 g/ha) for tsetse fly (Glossina spp.) control, on epigeal ants in mopane woodland in north-western Zimbabwe. Twenty species of ants were recorded at dishes baited with various types of food. Pheidole spp. and Monomorium opacum Forel (Formicidae: Myrmicinae) were predominant, both in the number of baits attended and in the number of workers present at individual baits. Season apparently had a greater effect on the composition and activity of the ground foraging ant assemblage than did either pesticide. There was a decline in the rate at which baits were found and in species richness of the ant assemblage as the dry season progressed and several species also showed changes in their ability to locate baits. There was no major pesticide induced disruption of the species richness or food finding ability of the diurnal ground foraging ant assemblage sampled. However, foraging success by Platythyrea cribrinodis (Gerstaecker) (Formicidae: Ponerinae) was reduced immediately after spraying with deltamethrin. Subtle effects of either insecticide on rarer species cannot be discounted from the results of this study.

The relative contributions of host plant, herbivore species and clone to variation in the interaction between cereal aphids and wheat were investigated using five clones each of three species, Rhopalosiphum padi (Linnaeus), Sitobion avenae (Fabricius) and Schizaphis graminum (Rondani), on seedlings of two cultivars of Triticum aestivum L. and one cultivar of Triticum durum Desf. More individuals and biomass of R. padi than of the other two species were produced on seedlings. The three wheat cultivars lost similar amounts of biomass as a result of infestation by aphids, with the amount lost depending on aphid species: S. avenae caused the lowest loss in biomass. Variation in aphid biomass production was due mostly to differences among aphid species (70%), less to the interaction between wheat type and aphid species (7%), and least to aphid clone (1%). The specific impact of the aphids on the plants ranged from 1.7 to 3.7 mg of plant biomass lost per mg of aphid biomass gained, being lowest for R. padi and highest for S. graminum. Variation in plant biomass lost to herbivory was due mostly to unknown sources of error (95%), probably phenotypic differences among individual seedlings, with 3% due to aphid species and none attributable to aphid clone. For these aphid–plant interactions, differences among aphid clones within species contributed little to variation in aphid and plant productivity; therefore, a small sample of clones was adequate for quantifying the interactions. Furthermore, one clone of each species maintained in the laboratory for about 200 parthenogenetic generations was indistinguishable from clones collected recently from the field.

When engaged on some entomological research in the extreme north of New Zealand, Mr. J. G. Myers, of the Biological Laboratory, Wellington, was attacked by a large number of small biting flies, specimens of which he was kind enough to send me for study. I am much obliged to him for having thus given me the opportunity of making known a new biting species of Ceratopogoninae, and I have much pleasure in dedicating it to him.

The highlands of Abyssinia are remarkably free from blood-sucking flies, if the Culicidæ, Stomoxys, and Hippoboscidæ are excepted.

Flight activity characteristics of Chortoicetes terminifera (Wlk.) were recorded in adults suspended on a simple flight balance in a wind tunnel. Ninety-one per cent, of flights by post-teneral (>5-day-old) insects lasted less than 60 s, and only 11% of adults flew for a full 20-min test period at 30°C. The flight capacity ranged from a few or many short flights to continuous flights. Females flew for a greater proportion of the time than males. Flight activity increased with food-deprivation, and only fully hardened (>9-day-old) insects flew continuously throughout a 45-min test period at 26–41°C. Gravid females also made long flights. The frequencies of flight durations by laboratory-reared insects were strikingly similar to the day flight of milling field populations in eastern Australia. Flight performance observations indicated that lift declines with time in flight, wing-beat frequency initially being 33·2 Hz in males and 30·0 Hz in females. The results are discussed in relation to field studies.