In this article is recorded the finding of eggs of Ficalbia (Ficalbia) minima, Theo., which were hitherto unknown. A description of these eggs is given and they are compared with eggs of Mansonioides which occur in a similar situation.

For some years economic entomologists in Kenya and Uganda have recognised two species of Capsids of more than usual importance. Lygus simonyi, Reut., was a pest on coffee in Kenya, and Lygus vosseleri, Popp., was injurious to cotton in Uganda. The species were originally identified from the keys and descriptions of B. Poppius in his “Die Miriden der Äthiopischen Region” (Acta. Soc. Sci. Fenn. 41, no. 3, 1912, & 44, no. 3, 1914). This monograph although indispensable to anyone working on the systematics of the African Capsidae, is on the whole rather unsatisfactory. The illustrations are few and far between, the genera are often based on relative and overlapping characters and the specific differentiations are vague. It is not suprising therefore that the original determination of the coffee Capsid now proves to be incorrect. Thanks to the courtesy of Dr. Richard Frey, of the University Zoological Museum, Helsingfors, and Dr. Max Beier, of the Natural History Museum, Vienna, I have now been able to examine type material of these two species.

Lygus simonyi has been found to cause serious damage to cotton in Uganda, by sucking the young leaves and apical buds, by retarding the growth of the branches, and by sucking the young bolls.

There are indications that soil and climatic factors are of importance in controlling this insect ; excessive succulence of the plant appears to be one factor associated with severe damage.

1. G. swynnertoni is a source of danger to man and to cattle. Until reclamation was started it was rapidly advancing in the Shinyanga District and was driving the native population in front of it.

2. Round Shinyanga this species occurs in gently undulating country supporting four main types of vegetation, namely:— (a) a Commiphora Fischeri community found on the well-drained rises with a good grass growth ; (b) a Lannea humilis-Commiphora Schimperi community on low-lying hard-pan areas in which the grass is poor and patchy ; (c) communities in which the grass growth is good and the main trees are Acacia spp. ; (d) a plains community, partly treeless, partly covered with shadeless woods of the small gall acacias, which are swampy during the rains and very dry at other periods of the year ; during the dry season the trees are completely leafless, and very dry and severe conditions prevail.

3. Game is in moderate numbers throughout the year, so that there is no lack of food in any type of vegetation.

4. The majority of flies living in the hard-pan areas obtain and digest their food there. Flies behave similarly in the C. Fischeri association, but some of them whilst searching for food may encounter a hard-pan area, where they will continue their search for food. When they get food they may or may not return to the C. Fischeri association to digest it. If a fly strikes a road or open plain it will patrol this until it finds food, when it will return to more sheltered vegetation to digest it.

5. G. swynnertoni is mainly a thicket-breeder, though pupae are also found under decumbent logs, overhanging rocks and in hollows at the bases of trees. Where the C. Fischeri was much broken up by valleys of hard pan, breeding was found to be taking place to the same extent in the thickets of both of these types.

6. G. swynnertoni is commonest in hard pan, much less common in C. Fischeri, scarce in the Acacia bush types worked in Shinyanga, and least common in the open plains.

7. When flies are numerous, each of the first three types enumerated in (2) is able to support a fly-community. When the flies are scarce, the C. Fischeri and the Acacia communities lose their flies to the hard pan and hence are little infested. The hard pan is to a far greater degree self-contained as regards the requirements of the fly.

8. G. swynnertoni is commonest during the first month or two of the dry season. As the dry season progresses it decreases in numbers and reaches its minimum during the short rains. There is a rise in the short dry season following the improvement of conditions brought about by the early rains ; after this numbers remain fairly constant until the end of the long rains. Hunger and female percentage are least in the beginning of the break of the short rains.

9. There is no indication that the concentrations of fly in the hard-pan areas disperse at the end of the rains.

10. Like Glossina morsitans, G. swynnertoni appears to find food by sight rather than by scent. The part that scent plays in the matter has hardly been finally elucidated.

11. G. swynnertoni is capable of crossing an 800 yards clearing without the assistance of game, irrespective of whether the clearing passes over alluvial or eluvial soil. It is the hungry flies mainly that cross. They are presumably searching for food.

12. The hungrier a fly is the more persistent it is in following man. Males are more persistent followers than females.

13. An experimental attempt was made to exterminate G. swynnertoni by hand-catching off screens in a block of 15 square miles during sixteen months. Reduction in numbers occurred, but flies continued to exist in the block because the isolating clearings were too narrow. Further, female flies do not appear sufficiently readily to catchers, so that breeding is able to continue.

14. A very large rise in female percentage occurred. A similar but lower rise marked an experiment in the catching-out of G. palpalis by hand on Mugasiro Island, near Musoma, by Robert Koch in 1913. In this the catching was off man only.

1. Attention is drawn to the presence of Liothrips vaneeckei upon lilies in this country and reference is made to its known distribution and host plants.

2. The various stages of the thrips are described and figured.

3. The life-history and habits, together with the injury caused, are discussed.

4. Control measures are considered. A method of fumigation with paradichlorbenzene is described, and the necessary apparatus to employ and technique to observe when fumigating upon a commercial scale are outlined.

Such knowledge as we have of the family Lacciferidae is very largely embodied in an excellent monograph published in 1923 and 1925 by J. C. Chamberlin (Bull. Ent. Res. 14, pp. 147–212 and 16, pp. 31–41). The comparatively speaking limited geographical distribution of the various generic groups is well brought out in this monograph. Thus, for instance, the genera Tachardiella and Austrotachardiella are apparently confined to North and South America, Metatachardia to Ceylon, Austrotachardia to Australia, Tachardia to India and the Far East. Chamberlin further states (p. 149) “ in general it may be said that the species of this group are tropical or sub-tropical, apparently reaching their greatest abundance in regions of limited rainfall.” How far this comparatively limited and well-defined zonal distribution of the various genera will hold good as further material is collected will prove of the greatest interest.

Ten years have now elapsed since the first dusting operations by aeroplanes were carried out against forest insects in Germany. It is therefore a tempting task to try to review the development of this modern method of fighting forest insects and to formulate, at least tentatively, some fundamental conceptions regarding the specific conditions which must be fulfilled before this method is resorted to.

This paper is based on material submitted for identification by the Imperial Institute of Entomology and received from Mr. G. H. Corbett, Government Entomologist of the Federated Malay States.

1. All the species of Siberian grasshoppers that have been studied in sufficient detail consist of a series of races exhibiting parallel coloration, structure and behaviour characters.

2. Every race of Chorthippus albomarginatus, Zett., Aeropus sibiricus, L., and of other species, has in its hopper and adult stage a series of colour forms analogous in their characters to the phases solitaria, transiens and gregaria of swarming locusts.

3. These colour forms are very unstable and undergo changes during the individual life due to the conditions of breeding.

4. Breeding in crowded conditions results in the predominance of dark-coloured forms, with black and sometimes with orange spots. Breeding in isolation, on the contrary, results in light forms of various colours.

5. No complete transformation of all the individuals in a population is observed in Siberian grasshoppers, and the intermediate forms represent a considerable portion of every population.

6. These colour forms, which can be considered as phases, differ also in their structural characters. Phase gregaria is larger and more long-winged than phase solitaria.

7. The phases differ further in their behaviour, ph. gregaria being more mobile and inclined to migrations, than ph. solitaria.

8. Every species and every race which have been studied exhibit a potential ability to produce phases, but this ability is not equal in all species and races. Those species and races which, owing to their habits and to the conditions of their habitats, can multiply in masses in restricted areas are more inclined to phase variability.

In 1930 the available information regarding gall midges as enemies of the Coccidae was summarised in a paper published in the Bull. Ent. Res. (21, 1930, pp. 319–329). Since that time there have been several additions to our knowledge concerning such midges. Some of this knowledge was cited as an addendum in a later paper on gall midges as enemies of mites (Bull. Ent. Res. 24, 1933, pp. 215–228). It is proposed in this paper to bring this subject up to date by referring to published work and by describing some new forms that have been received for identification in the immediate past.

The mouth-parts of male mosquitos are referred to in many text-books, but the descriptions given by various authors differ to a quite remarkable extent. This fact is particularly noticeable in regard to the maxillae and the mandibles. It is usually (and correctly) pointed out that maxillae are present in the male proboscis ; but the statements made by different observers concerning the length of these organs are extremely discordant. As to whether the male proboscis contains mandibles in addition to maxillae, opinions are sharply divided, the majority of writers asserting (as we shall see, incorrectly) that such is not the case.

The paper deals with the control of insects by hand-collection. An experimental study of the method as used against Antestia on coffee in Kenya is described. The rate of increase of the yield of insects collected falls off in a definite and measurable manner as the time spent on the work increases. The formula for the curve fitting the results is P = 100(1 − (V.e.)−t) where “ P ” is the percentage collected of the total Antestia present, “ t ” is the time spent collecting, and “ V ” is a coefficient which has different values according to the conditions prevailing. In practice one careful experimental picking provides data for the calculation of the formula which may be used to determine the cost of hand-picking any percentage.

The results show that in theory 100 per cent. of the insects can never be obtained by hand-picking, and that in practice the cost of picking an adequate percentage is almost invariably prohibitive.

It is probable that the experimental results obtained will prove valid in other cases of hand-picking. Much of the expenditure on this method is unproductive.

Details of a thorough long-continued attempt to control Antestia on thirty-five acres of coffee by hand-picking are given. The attempt proved unsuccessful, and it is suggested that it may actually have been responsible for the maintenance of the severe attack.

The kind co-operation and assistance of a number of coffee planters are acknowledged. Except for the first experiments in 1933 Mr. H. Naismith Jones assisted me throughout, and the investigation owes a great deal to his careful supervision of much of the field work.

In the course of some work at Rothamsted on the activity and abundance of insects, in which a light trap was used as a method of estimating the numbers of insects in a state of activity, it appeared advisable to have a further trapping method which did not depend on phototropic response for its efficiency. A rough design for a mechanical trap was therefore drawn up by the senior author.

During investigations on the ecology of Aphids infesting the potato crop it became necessary to study the precise effect of the different meteorological factors upon migration. Traps, treated with adhesive material, which depended on a wind-vane to keep them at right angles to the direction of migration were first used but proved unreliable, since it was found that aphis migration attains a maximum when there is little or no wind. Kites, also, proved impracticable for the same reason. It was, therefore, essential to construct a trap which worked independently of meteorological conditions. I am indebted to Dr. C. B. Williams and Mr. P. S. Milne, of Rothamsted Experimental Station, for the opportunity of discussing and examining the construction of their electrical mechanical trap, described in the preceding paper, which formed the basis of one constructed at the College Farm, Aber, near Bangor. Since, however, the village of Aber has no electricity supply it was necessary to alter, materially, the mode of construction in order to drive the trap by water-power. For this reason and, since the modified form can be used in districts where there is no electricity supply, it was suggested that the present account of the water-power mechanical insect trap should be published along with the description of the Williams and Milne trap. I am, therefore, grateful to the authors of the preceding paper for the opportunity of seeing their manuscript, thus avoiding, by reference, repetition of the description of several parts.

The excretions of the blowfly maggot, Lucilia sericata, have been found to contain a potent bactericide, and the technique for the collection of this material is given. There is evidence that other insects besides the one investigated may also produce this substance.

The active principle is not destroyed by autoclaving at 10 pounds' pressure for 20 minutes and desiccation does not inactivate it.

The bactericidal action of the substance was demonstrated by tests on seven species of bacteria, most of which are of aetiological importance in osteomyelitis and other suppurative infections. The lethal action against such organisms seems to be an important factor in the good results obtained with maggot therapy.

The work seems to open a field in which interesting investigations could be conducted with possibilities of producing other new and useful disinfectants from living organisms.

Dermatodes cinchonae, sp. n.

♂♀. Derm black or piceous, with uniform dense brown scaling above, becoming paler laterally and beneath.

For several years the Farnham House Laboratory of the Imperial Institute of Entomology has been making a study of the parasites of Diprion spp., in order to acclimatise the most important of them in Canada. Dr. K. R. S. Morris has been specially engaged on this investigation in Czechoslovakia and Hungary, and this year (1935) has discovered some parasitised eggs of Diprion sertifer, Geoffr. Almost at the same time, other eggs of the same host, sent from Sweden, were found to be parasitised by some Chalcids, but belonging to another species. Experiments are actually being made to breed and acclimatise these two species in Canada. Both are Chalcids belonging to the family Eulophidae, sub-family Entedoninae. As very little is known about these egg-parasites of sawflies, we are giving notes and descriptions of these two species, of which one proved to be new.

Camponotus compressus, the common black ant (fig. 1), is one of the most abundant and best known species of ants in South India. The worker is a large jet-black ant ranging in length from 6 to 16 mm. with moderately large eyes, brownish legs and antennae and a prominent shining abdomen. These ants live in enormous communities, travelling long distances from their nests, and are active at all times of day and night. Though ordinarily of a peaceful disposition, when alarmed or disturbed they may display a tendency to be quarrelsome.