A short tour of northern Darfur was made by the author, on behalf of the Imperial Institute of Entomology, with the object of observing the solitary Schistocerca population, comparing it with that of northern Kordofan, and looking for any factors which might indicate the presence of potential outbreak centres of the desert locust.

The present study was carried out to unveil interactive relevance among consecutive and alternate members of a tritrophic system comprised of sugar beet genotypes, beet armyworm, Spodoptera exigua (Hübner), and its parasitoid, Habrobracon hebetor (Say) using demographic parameters. To do so, H. hebetor was reared on S. exigua fed on 10 sugar beet genotypes, including SB26; SB27; SB29; SB33; SB34; (7112*SB36)*Sh-1-HSF-5; FC220; FC301; SBSI006; and HM 1339RZ in a growth chamber at 25 ± 1 °C, 60 ± 5% RH, and 16:8 (L: D) h photoperiod. The data was analyzed based on the age-stage, two-sex life table theory. Our results revealed high variation in duration of different life stages of H. hebetor on S. exigua reared on different sugar beet genotypes examined. The shortest (10.605 days) and longest (13.721 days) pre-adult period of H. hebetor was on S. exigua reared on SB26 and SB34, respectively. The longest (17.2 days) and shortest adult longevity (7.5 days) was on S. exigua reared on SB26 and SB27, respectively. The highest values of the intrinsic rate of increase (r) (0.209 day−1) and finite rate of increase (λ) (1.233 day−1) were observed on S. exigua reared on SB34 and their lowest values (0.159 and 1.172 day−1, respectively) were recorded on SB27. Resistant and susceptible genotypes to S. exigua, FC301 and (7112*SB36)*Sh-1-HSF-5, respectively, were only genotypes on which H. hebetor had greater and approximately equal r compared with S. exigua. This finding indicates high capability of H. hebetor to be successfully employed against S. exigua on sugar beet genotypes which are extremely different in resistance to this pest.

The mosquito fauna of New Caledonia and the Belep Islands is discussed, together with some features of the larval morphology of Culex (Culex) pipiens fatigans Wied., C. (C.) annulirostris Skuse and C. (Neoculex) pseudomelanoconia Theo. Culex (C.) bitaeniorhynchus Giles, herein recorded from New Caledonia for the first time, is probably a post-war introduction into the Noumea area from Australia. Culex (Lophoceratomyia) fraudatrix Theo., recorded from Art Island (Belep group), has not previously been known from the New Caledonian area. From the mosquito and blood-smear survey in the Belep Islands, it is concluded that these islands, like New Caledonia, are as yet free from Anopheles and malaria.

Samples of 25 African populations of Aedes aegypti (L.) were examined for variations in scale-colour pattern of palps, halteres, abdominal tergites and metatarsi and in larval body colour. A colour index based on these characters showed domestic populations to be paler than populations found in forests. Classification of phenotypic and genotypic variations in the amount of pale scaling on palps, halteres and, especially, tergites revealed statistically significant differences between some of the populations. Although it was impossible to identify individual mosquitoes, population samples could be identified according to subspecific designations as A. a. formosus (Wlk.) and A. a. aegypti.

(1) An effort has been made to find an explanation for certain problems involved in the selection of breeding-places of mosquitos in Queensland.

(2) Many of these problems must remain unsolved until it is possible by patient study of local conditions to bring all the factors involved into play.

(3) In order to explain the reason for the avoidance of natural water, where it exists, it is suggested that the soils that underlie them should first be taken into consideration, and that the waters should be examined with reference to their physical and chemical conditions.

(4) Observations and experiments, spread over a period of eighteen months, confirm the findings of previous authors that Characeae do not in themselves possess larvicidal properties.

(5) That food is the main determining factor in the choice of preferential breeding-places seems to be borne out by actual results obtained, and that when such are not available, mosquitos will resort to breeding-places of compulsion, such places being usually observed to be entirely or partly devoid of food supplies.

(6) It is suggested that the salts of alumina and iron in the ferrous state tend to destroy food organisms, and that where these conditions exist, the water is not selected preferentially.

(7) The presence of algae leads to the appearance of Anopheles annulipes.

(8) That Cladophora holsatica inhibits larval growth seems to be experimentally established.

(9) Bacterial scums are mainly due to B. subtilis and have a tendency to produce a slight alkalinity.

The best way of preventing locust outbreaks is to control them at their source. After a description of those habits of the Red Locust that have a direct bearing on control, an account is given of some of the results of three years' experience of control of this species in an outbreak area. The methods used in Rukwa are described in detail, and attention is drawn to their relative efficacy, advantages and difficulties. A number of other methods are also referred to and their values discussed. Control methods are considered with special reference to conditions in Rukwa and other outbreak areas, and in relation to large scale campaigns against large outbreaks. Conclusions on the relative values of the various methods are summarised below. These values depend both on the habits of the locusts and on the ecological, economic and social conditions of a country in which a campaign is to be waged. It must not be assumed that conclusions about control methods reached with one locust or in one country necessarily apply to another locust or another country.

Immature fruit fly stages of the family Tephritidae are commonly intercepted on breadfruit from Pacific countries at the New Zealand border but are unable to be identified to the species level using morphological characters. Subsequent molecular identification showed that they belong to Bactrocera xanthodes, which is part of a species complex that includes Bactrocera paraxanthodes, Bactrocera neoxanthodes and an undescribed species. To establish a more reliable molecular identification system for B. xanthodes, a reference database of DNA barcode sequences for the 5’-fragment of COI gene region was constructed for B. xanthodes from Fiji, Samoa and Tonga. To better understand the species complex, B. neoxanthodes from Vanuatu and B. paraxanthodes from New Caledonia were also barcoded. Using the results of this analysis, real-time TaqMan polymerase chain reaction (PCR) assays for the detection of B. xanthodes complex and for the three individual species of the complex were developed and validated. The assay showed high specificity for the target species, with no cross-reaction observed for closely related organisms. Each of the real-time PCR assays is sensitive, detecting the target sequences at concentrations as low as ten copies µl−1 and can be used as either singleplex or multiplex formats. This real-time PCR assay for B. xanthodes has been successfully applied at the borders in New Zealand, leading to the rapid identification of intercepted Tephritidae eggs and larvae. The developed assays will be useful biosecurity tools for rapid detection of species in the B. xanthodes complex worldwide.

In India the economic rôle played by insects of the order Thysanoptera, popularly known as “ thrips,” has not become so conspicuous as in some other parts of the world. The different kinds of thrips affecting specific crops such as wheat, oats, tobacco, fruits, onions, cacao and hot-house plants, in Europe, America, the West Indies and many tropical areas, are insects of established notoriety, and some of them cause severe and extensive damage to valuable crops from time to time ; but so far no species of Thysanoptera has as yet gained such prominence in India. Neither Lefroy in his book on “ Indian Insect Pests ” (1904), nor Fletcher in his publication on “ South Indian Insects ” (1914), has recorded any insect of this group as a definite pest among the numerous forms listed as injurious. In his other and more voluminous text-book, “ Indian Insect Life ” (1909), however, Lefroy, in the course of a brief chapter devoted to Thysanoptera, just refers to the three Indian species which were the only ones recorded till then, viz. : Idolothrips halidayi and Phloeothrips anacardii, described by Newman in 1856, and Panchaetothrips indicus, described by Bagnall in 1912 ; and only one of these, the last, had any economic importance, having been noted on turmeric in Madras.

Results are given of investigations on the effects of five post-treatment temperatures on the mortality of adults of Tribolium castaneum (Hbst.) sprayed with five or six concentrations of each of six insecticidal formulations, emulsified solutions of DDT, γ BHC, toxaphene, chlordane and parathion and a suspension of DDT.

With both emulsified solutions and suspensions of DDT and emulsified solutions of γ BHC the mortality of the insects decreased with the rise of temperature from about 14° to 30°C. and increased when the temperature increased from 30° and 40°C. On the other hand, with emulsified solutions of toxaphene, chlordane and parathion, the mortality of the test insects increased continuously with increase of temperature from 14° to 40°C. As a possible explanation for such divergent results with different insecticides it is tentatively suggested that whilst the inherent physiological resistance of Tribolium to DDT and γ BHC formulations which appear to increase with increase of temperature up to a certain point has been demonstrated, the technique has not been sufficiently critical in the case of the other formulations, and it is thought that physiological resistance has possibly remained masked by other factors and that the values of LC50 are not a true index of physiological resistance in the ease of these insecticides.

An essential similarity between the curve obtained by plotting values of LC50 against temperature in the case of DDT and γ BHC and those relating temperature to other physiological activities (published by various workers) has been stressed, implying a similarity between the resistance of the insect to insecticides on the one hand and its other physiological activities on the other.

Sinoxylon senegalense is essentially the wood borer of felled Acacia seyal Del. in the Sudan, damage due to other beetles being contributory in a very small degree.

The life-history of the Bostrychid is recorded. The period from egg to adult is about eight weeks, but the complete life-cycle is considerably longer. The larval tunnels are superficial and only a few inches in length. The damage is almost entirely due to the adult, which remains boring within the logs for nearly 10 months. A predacious Clerid, Cylidrus fasciatus, and Braconid parasites, a species belonging to genus near Doryctes and Platyspathius pictipennis, were recorded.

Destruction of the timber is very rapid and control methods should be undertaken as soon after felling as possible. Insectaries were prepared containing the timber treated in various ways and the behaviour of the insect noted in each instance. The chemicals used in the experiments were sodium arsenite, boracic acid and pentachlorophenol. The latter, used as a spray on barked logs, was found to be the most effective.

This report, which is of a preliminary nature, deals with the species of Culicidae met with in Macedonia by the British Malaria Commission during the latter half, of 1917. The collections of the Commission have been augmented by material forwarded from time to time to the Malaria Enquiry Laboratory, Salonika, by various Medical Officers and others in the field. While engaged in working out these and other blood-sucking Arthropods, I had the privilege of examining, through the kindness of Dr. Joyeux, of the Mission Antipaludique, samples of species taken within the areas under French control. As our reports are to appear almost simultaneously, and as my colleague has devoted special attention to the larval morphology of these insects, I have confined myself here mainly to the adults, and field notes. I desire to thank heartily the following officers for material and notes supplied—Majors Bissett and Armour; Captains Boyd, Candler, Peacock and Carnwath. I have also been indebted in many ways to the kindness of Lt.-Col. C. M. Wenyon, O.C. the Malaria Enquiry Laboratory. For the work of identification the Trustees of the British Museum (Nat. Hist.) have afforded every facility, and in this connection my best thanks are due to Mr. Lang of the Museum Staff. Again, as on many another occasion, it is a pleasure to acknowledge the assistance ungrudgingly rendered by Dr. G. A. K. Marshall, Director, Imperial Bureau of Entomology.

A long-horned beetle, Cerambyx dux, Fald., is a very serious pest of apricots, peaches, and grafted and wild almonds in Palestine. Its ravages are most probably not confined to these trees and further investigations will undoubtedly enlarge the already important list of food-plants. In localities around Jerusalemsuch as Beit-Jala, Artas, Bethlehem, El Maliha, and Ein Karim (approximate altitude 2,600 feet above sea-level), this pest has been allowed to establish itself over a long period of time and to such an extent that, if immediate and rigid control measures are not undertaken by the growers, apricot and peach trees will, sooner or later, disappear from these localities. These fruit trees can be cultivated without irrigation, which is of great advantage in Palestine, where water is scarce; the fruit fetches good prices both in the local markets and also in Egypt. Their cultivation is therefore of vital importance,especially to the population of the hill country, where conditions of life are difficult and every kind of loss is accentuated. In Jersualem, where almonds, apricots and peaches are planted in household-gardens, not a single healthy tree can be found, and many of them have already succumbed to the attacks of this beetle. In the coastal plain the writer has found this insect in almond trees at Haifa and in apricot and almond trees in villages north of Acre. No records are available of its presence in the coastal plain south of Haifa or in the Jordan Valley.

Studying aquatic benthic macroinvertebrates (BMIs) in the field requires accurate taxonomic identification, which can be difficult and time consuming. Conventionally, head capsule morphology has been used to identify wild larvae of Chironomidae. However, due to the number of species and possible damage and/or deformity of their head capsules, another supporting approach for identification is needed. Here, we provide hemoglobin (Hb) protein in hemolymph of chironomids as a new biomarker that may help resolve some of the ambiguities and difficulties encountered during taxonomic identification. Chironomids collected from two locations in Maine and New Jersey, USA were identified to the genus level and in some cases to the species-level using head capsule and body morphologies. The head capsule for a particular individual was then associated with a corresponding Hb protein profile generated from sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS–PAGE). Distinct Hb profiles were observed from one group (Thienemannimyia) and four genera (Chironomus, Cricotopus, Dicrotendipes, and Glyptotendipes) of chironomids. Several species were polymorphic, having more than one Hb profile and/or having bands of the same size as those of other species. However, major bands and the combination of bands could distinguish individuals at the genus and sometimes species-level. Overall, this study showed that Hb profiles can be used in combination with head capsule morphology to identify wild chironomids.

All stages of Argas persicus were found in crevices in the bark of 49 of 266 trees belonging to 16 species in West Pakistan. These trees had not been used as roosts by domestic birds. The infestation seemed to be restricted to those trees used by vultures (Pseudogyps bengalensis) or herons (Ardea cinerea) for nesting or roosting. Several of the ticks collected contained recently sucked avian blood in the gut but intramuscular injection of crushed material from the ticks into a hen produced no blood infection.

Infested trees may be important as sources of the pest near poultry farms and chicken houses.

A study of the genitalia of both sexes of the Queensland pink bollworm, Pectinophora scutigera, Holdaway, originally named from the immature stages, has confirmed the validity of the species. Details of a comparative study of the genitalia of this species and Pectinophora gossypiella, Saunders, are given and figured.

Though our knowledge of this remarkable insect remains far from complete, fresh material, procured through Dr. C. F. C. Beeson, has enabled me to throw more light on its envelopment and to correct some misinterpretations in my earlier article (Bull. Ent. Res., xvii, p. 55, July 1926).

Studies in Queensland showed that an outbreak of Austrosimulium pestilens Mack. & Mack. occurs if the water-level in a river rises enough to release eggs buried in the river-bed. Following such a rise, the larval development of A. pestilens was completed in 6–7 days in summer and 9–10 days in winter, and after a pupal period of 1·5–2 days in summer and 3 days in winter, adult eclosion began. Most flies emerging during the first 1–2 days were males, but females were slightly predominant later. A. pestilens emerged throughout the diel; at night there was a drop in the numbers emerging, and this was followed by a distinct early morning peak. Following a rapid rise and fall in river-levels, adult eclosion and mating occurred over a period of several days early in an outbreak, but after high river-levels of long duration, eclosion and mating occurred over a much longer period.

In Bulletin No. 28 of the Technical and Scientific Service of the Ministry of Agriculture of Egypt I described a new type of light trap for collecting insects which had the advantages that the insects were rapidly killed in good condition for identification, that the light was visible in all directions, and that it could be used with either electricity or acetylene by an untrained worker.

A number of liquid mosquito repellents were assessed for vapour repellency power in an olfactometer mounted in a very large cage filled with females of Aëdes aegypti. They were also tested for their knockdown power in fumigation bottles. Their vapour pressures were determined by the Ramsay-Young method.

All the liquids showed vapour repellency, and in 39 out of the 42 tested this effect was highly significant. The highest vapour repellency ratings were shown by compounds already known to be the most effective repellents.

Although the more volatile compounds such as citronellal tend to show the highest repellency ratings, nevertheless compounds of low vapour pressure such as indalone, DMP and isobornyl morpholinoacetate may also show high vapour repellency. It is concluded that vapour repellency, although in the first instance dependent upon volatility, can vary independently of vapour pressure, so that compounds may be found which afford not only a long protection period due to their nonvolatility, but also a high vapour repellency due to the potency of the comparatively few molecules that are volatilised.

The vapours of most of the repellents were found to induce knockdown of mosquitos, but there was no correlation between the speed of this process and the vapour repellency of the compounds.

Records of termites attacking growing crops in Saudi Arabia have so far referred to Microcerotermes diversus Silv., one of the subfamily Amitermitinae of the Termitidae (Ayoub, 1959). This termite is also known from the Yemen, the South Arabia Federation and Iraq.