Poeciloscytus cognatus, Fieb. (fig. 1) has already been recorded as injuring sugar-beet in Ukraine. In the summer of 1926 an enormous number of these bugs appeared quite unexpectedly in the districts of Poltava and Kharkov and caused great losses. Much attention has been given to methods of control on the plantations, but the following information is only of a preliminary nature and refers partly to the phenology of the insect.

Aëdes argenteus, Poiret, is a very variable mosquito, and it was thought that it would be interesting to examine a number of freshly-hatched and therefore undamaged specimens and to note how many conformed to the original description. No difficulty was experienced in obtaining the necessary material, as collections of larvae are received daily from the Medical Officer of Health. One thousand of each sex of the species were mounted in the order of their emergence from the pupal case and were examined under the binocular microscope. The one constant feature was found to be the lyre-shaped marking on the thorax, although even here the outline and the centre lines varied in breadth and in colour, and the centre lines varied in length. But as the abdomen and the hind tarsus showed the greatest variations, the present paper is restricted to a description of these.

The importation of parasites from the native home of introduced insect pests now constitutes a recognised part of entomological practice in most countries under civilised control. However, since the method is still in the experimental stage, and since long periods of time often elapse before the parasites colonised become sufficiently abundant to exert any appreciable influence on the host, the entomologist often finds it necessary, in order to avert disaster, to utilise remedies which, though temporary, are more immediately effective. To this end he employs some one or other of the various methods of mechanical control, by which the population of the insect pest can be at once greatly reduced.

But in many cases, these methods of attack affect the parasites as well as the hosts. It is therefore important to consider what influence they will have upon the progress of the natural enemies and whether, in order to obtain the temporary relief afforded by mechanical methods, we are not sacrificing the hope of permanent control.

We have at present no data permitting us to attack this problem from the experimental angle ; but it can be studied in a broad general way when reduced to mathematical terms.

During the six-month period from December 1925 to June 1926, some observations were carried out on the mosquito breeding that occurred in a number of “ test ” water-containers placed in various locations in the compound of the headquarters of the West Africa Yellow Fever Commission at Yaba, near Lagos, Nigeria. The main purpose of these observations was an endeavour to obtain supplemental information on the bionomics of the yellow fever mosquito, Aëdes (Stegomyia) aegypti, Linn., in West Africa.

During two years (1924 and 1925) spent in Samoa by Dr. P. A. Buxton and myself, while employed in research on filariasis for the London School of Hygiene and Tropical Medicine, we made notes of such agricultural pests as came our way, though (our main interests being medical) we were not able to investigate them at all thoroughly. For this reason the fact of an insect being recorded only on one occasion is no indication that it did not occur in other months, or even that it was uncommon, since we frequently did not continue to make notes of the occurrence of a species we had once recorded. Though our observations make no claim to completeness, they are perhaps worthy of publication in view of the scarcity of records from this group of islands. Our observations on medical and veterinary entomology have been published as a Memoir of the London School of Hygiene and Tropical Medicine. In that Memoir we have published maps, and short accounts of the structure, flora and climate, of Samoa.

Microbracon kirkpatricki, sp. n.

♂♀. Pale reddish testaceous with the 1st and 2nd tergites often almost stramineous ; antennae of a darker red ; extreme apex of tarsi black ; ovipositor sheaths dark brown to black ; the male often with the 2nd–5th tergites discally brownish ; ocelli black, the ocellar area sometimes darkened ; legs, particularly the hind legs, often stramineous or nearly so ; stigma and wing veins pale reddish, except that in the forewing the 1st abscissa of the anal vein and the basal half of the 1st abscissa of the medial vein are virtually colourless, and that the costal vein is brownish, and that the stigma in the males is brownish.

♀. Integument noticeably coriaceous throughout, except the appendages. Head broadly rounded behind, 1·75 times as broad as long ; ocelli on a more or less distinct tubercle, not close together, the posterior ones only somewhat nearer to one another than to the eye ; flagellum with 25–29 joints, the majority of specimens with 27–29 joints ; apical joint of antennae wth a short apical style ; head impunctate and narrowly coriaceous. Thorax impunctate, with mesonotum, scutellum, and propodeon, more broadly coriaceous than the head ; mesopleurae more broadly coriaceous again ; the lines of the notauli only faintly indicated, but noticeable, chiefly on account of the enclosed median area which is raised somewhat and which, tapering to a point, reaches almost to the scutellar depression ; scutellar depression apparently sometimes weakly crenulate and sometimes plain ; propodeon completely plain except for a median, very weak, longitudinal excavation extending about half the length of the propodeon, when it becomes a fairly well marked longitudinal carina which extends to apex, where it joins the transverse apical ridge.

During November 1926, a few days were spent in making a rapid investigation of the insect pests of cotton occurring on the coast of Kenya Colony, between Mombasa and Mambrui, some eighty miles to the north.

The pink boll-worm, Platyedra gossypiella, Saund., was found to occur in every plot of cotton visited ; it was also noticed that a certain proportion of the worms were parasitised by a species of Braconid, which has been described above by Mr. D. S. Wilkinson under the name of Microbracon kirkpatricki.

A second visit was paid to the coast during the beginning of February 1927, to ascertain to what extent, if any, the pink boll-worm was controlled by this parasite, and to report on the possibilities of its introduction to other countries.

Owing to the short time available for this work, these notes are naturally very incomplete ; it is hoped however that they will be of some value should anyone be of the writer's opinion that it is well worth while attempting to introduce this parasite into other countries.

During 1925–1926 a number of tulip bulbs and iris corms infested with Aphides were received from various sources, as well as Aphides from growing tulips. These species were reared and observations made on the progress of the infestation on tulips. It is evident that one species Anuraphis tulipae (B. de Fonsc.) is a serious pest of stored bulbs, especially tulips, and another species, Rhopalosiphoninus tulipaella (Theo.), may also be of importance in this respect. Since these two species are not well known, it may be desirable to give detailed drawings of the species together with some notes on the observations made. It is hoped that the complete life-cycles and alternative food-plants of these species may be traced later.

In addition to the two species mentioned above, Macrosiphum gei (Koch) and Myzus persicae (Sulz.) were also found infesting tulips.

In the course of the beekeeping work of this Department we have had a number of hives weighed at regular intervals of about a week by means of a steelyard and tripod, and two permanently standing on platform weighing machine and weighed every day. The information obtained from these has been of great value in showing the seasonal variation in activity, the periods of honey flow, and the effect on the hives of the presence of enormous numbers of hornets in the late summer.

There were, however, many problems, such as the daily periods of activity and honey-collecting, the effect of high midday temperature, etc., that could only be dealt with by more frequent weighings, and it was felt that a machine to record continuously the weight of the hive by means of a rotating clock drum and pen would be a most valuable instrument of research.

The present paper contains the descriptions of two new species of mosquitos from North Queensland, Mucidus chrysogaster and Aëdes (Finlaya) mackerrasi. The former, the second Australian species of the genus, is a very interesting and most beautiful insect, of which only the female is so far known ; the latter is also of interest in that it adds yet another species to the closely interwoven group of Australian Finlaya.

My thanks are specially due to Dr. I. M. Mackerras, B.Sc., for his kind assistance in the determination of the latter species, since I was unable to do so myself, as the Institute does not possess a male specimen of Aëdes (Finlaya) occidentalis (Skuse). The comparative notes on the genitalia are from his pen.

Simulium bancrofti, Taylor (Plate V, figs. 1–5).

Head : Width of the frons slightly less than half that of the whole head ; antennae short, about two-thirds the width of the head ; first three segments cyathiform, the first slightly broader than long, a little less than half the length, and slightly more than half the width of the third ; second segment one-third longer than wide ; segments 4–7 inclusive approximately the same length ; the fourth a little wider than segments 5–7, which are all of about the same width ; penultimate longer than 4–7 individually ; apical segment moderately long and somewhat cone-shaped. Palpi five-jointed ; first joint cyathiform, with an apical row of four bristles, the two outer ones longer than the second segment ; the latter oblong, its sides nearly parallel, also with an apical row of bristles of about the length of the inner two on the first segment ; first and second segments together half the length of the third, the latter somewhat obovate, tapering slightly distally ; fourth almost pear-shaped, tapering basally, shorter than the third (11 : 14) ; fifth fusiform, tapering to a blunt point at both extremities and very little longer than the third, with a few scattered hairs, especially on its apex. Legs : fore femora and tibiae dilated ; first tarsal joint tapering very slightly at its base, a little more than half the length of the tibia (27 : 46), outer edge with a dense fringe of spinules, except on its basal fifth, apex with a stout spine on its outer apical angle ; base of second joint narrower than apex, lower surface with numerous spinules, especially on the distal two-thirds, apex with two stout spines, one on either side ; third and fourth joints cyathiform, the former one-third longer than the latter ; fourth with a deep median depression for almost half the length of the tarsus, forming the socket of the fifth ; third joint with numerous spinules on its distal two-thirds and an apical row of moderately long spines, the outermost the longest ; fourth joint sparsely covered with fairly long hairs, apex with four long, stout bristles, two on either side of the base of the fifth joint ; the latter pear-shaped, a little more than twice the length of the fourth, with a few fairly long hairs on its distal half ; claws short, almost straight, not toothed. Mid leg with the tibiae dilated, with a long, stout, external, apical spine ; first tarsal joint not dilated, a fringe of spinules along its outer margin and a few scattered ones over its ventral surface ; second joint with the spinules on the outer margin increasing in length and stoutness apically ; third joint similar to that of fore leg and without spinules ; fourth and fifth similar to those of fore leg ; joints 2 to 5 distinctly hairy.

Two previous lists of Parasitic Hymenoptera of economic importance have been prepared and published by the writer—one in 1919 and another in 1921 ; these included some of the more important of the economic forms then noted. During the last two or three years further work in this line was continued and additional data have been collected. In this paper an attempt is made to bring together in one incorporated list all the forms hitherto recorded from South India, at the same time revising the previous lists wherever necessary and adding recently collected data or data omitted from the two previous lists. It is believed that this revised list, with the available bionomical and synonymical notes, may be of some use for purposes of reference to those interested in this line of work. The writer takes this opportunity of expressing his thanks to the authorities of the Imperial Bureau of Entomology, London, and of the United States National Museum, Washington, for the help received from them in identifying some of the forms submitted to them, and confirming or correcting some of the identifications made at Coimbatore.

The pink bollworm of cotton in recent years has become so extensively distributed and is of such general, world-wide importance that its exceptional status in Haiti may prove to be of more than local interest.

Haiti is the western third of the island of Hispaniola, which is the second largest of the West Indies, lying between Cuba and Jamaica on the west and Porto Rico on the east. The Dominican Republic occupies the remainder of the island, and is sharply contrasted with its smaller but more populous neighbour in the language, racial origins, habits and customs of its people. Cotton is not extensively grown in the Dominican Republic ; in Haiti, however, it is second only in importance to coffee. The extensive plains of the Cul-de-Sac and the Artibonite seem to be especially well adapted in soil, elevation, and climate to its growth, and here it forms the main money crop of the region.

The purpose of this paper is to place on record my notes on the distribution of the mosquitos obtained by myself during an Expedition to Central Abyssinia made, in company with Mr. J. Omer Cooper, from September 1926 to January 1927. We were engaged in collecting insects of many Orders and some other animals, as well as plants, so that it was not possible to devote more than a limited time to Culicidae. Nevertheless, I purposely gave rather special attention to this family and got together a series of some 103 specimens of the adult insects, belonging to 13 (or possibly 14) species. Examples of each species were pinned immediately, when freshly killed, with fine pure-silver pins, while in a few places where large numbers of one species occurred the surplus specimens were placed in spirit. No detailed investigation of the larval or pupal stages was undertaken ; a few examples of these may later be forthcoming among the collection of aquatic organisms which are Mr. Omer Cooper's special province, but they are not dealt with here.

While our knowledge of the effects of variation of the physical conditions of the environment upon mosquitos is, in some directions, fairly satisfactory, in the case of the effects of variation of temperature there is lamentably little known. So far as a fairly complete survey of the literature dealing with mosquitos has revealed, there is only one paper specifically dealing with this matter, by Macfie (1920), although incidental observations have been recorded by other workers. This present paper is an outcome of an attempt to fill, to a slight degree, this lacuna in our knowledge. The investigations were carried out while the writer was attached to the Department of Zoology at the University College of North Wales, Bangor, and he has to express his thanks to Dr. C. L. Walton, Adviser in Agricultural Zoology, Department of Agriculture, Bangor, for allowing him to carry out the experiments in the Agricultural Zoology Laboratory.

The object of the present paper is to place on record a number of observations made by the writer in the Ibadan district of Southern Nigeria in the years 1922 to 1925, in the hope that they may be of some interest to other workers in Africa.

The writer wishes to acknowledge his indebtedness to Dr. G. A. K. Marshall and the specialists of the Department of Entomology in the British Museum for identifying the insects mentioned, and to Dr. A. W. Hill, Director of the Royal Botanic Gardens, for determining the majority of the plants.