The types of the four new species described below have been deposited in the British Museum (Natural History).

Thus far nine species of Anopheles have been found in Palestine. These, in order of frequency and importance, are : A. elutus, Edw., A. superpictus, Grassi, A. sergenti, Theo., A. multicolor, Camb., A. claviger, Mg. (bifurcatus, auct.), A. algeriensis, Theo., A. hyrcanus, Pall., A. pharoensis, Theo., and A. coustani, Lav. (mauritianus, Grp.).

The morphological characters of the eggs of these species have been described and are well known. Workers have, however, overlooked the fact that their eggs arrange themselves on water in specific patterns, determined apparently by their structure. Observations made during 1939–41 have shown that, if a number of eggs is placed on a drop of water, they assume a pattern characteristic of the species. This pattern arrangement makes possible a macroscopic differentiation of species in the field.

Observations have been made on ovipositions of all the species, but more particularly of A. elutus (188 ovipositions), A. sergenti (365 ovipositions), A. superpictus (149 ovipositions) and A. multicolor (51 ovipositions). These results indicate that these species arrange themselves into two types of patterns :—

i. Eggs arranged in parallel patterns. To this group belong those species that breed in open unshaded water : A. elutus, A. superpictus, A. multicolor.

ii. Eggs arranged in angular patterns, the eggs lying at an angle to one another, in the form of stars, etc. This group comprises the six remaining species, all of which prefer shaded places for their development.

For a study of population trends of Diarthrothrips coffeae, Williams, on coffee in Kenya, and to assess the value of sprays for its control, a method of sampling the population was required. This insect feeds on the leaves, green shoots, and berries ; but by far the greater part of the population lives on the leaves. Attempts to count the insects on the leaves in the field, by naked eye or with a hand lens, proved difficult and inaccurate. Two other methods were tried, those of E. A. McGregor (Pan-Pacif. Ent., 3, 1926, p. 29) and J. W. Evans (Bull. Ent. Res., 24, 1933, p. 349).The former proved unsatisfactory for several reasons such as the failure of the insects to forsake the leaves, the collection of debris on the grease tending to conceal insects, and the difficulty of counting the insects in the grease. The method of Evans was designed originally for obtaining the thrips from blossoms, but an examination of the method was made with the coffee thrips. Fairly consistent results were obtained with it, but the figures were low and it was clear that the sampling was not complete. It was found that a number of insects remained among the leaves and failed to reach the paper at the bottom of the cylinder. There are other disadvantages ; for example a large number of the cylinders are necessary to carry out a single spraying experiment, they are usually difficult to come by and the work of counting has to be done in the field, requiring a rather elaborate provision of tables and microscopes. Further it was found that even a light breeze was apt to cause loss of thrips during the counting.

(1) Two host-plants of Antestia lineaticollis in addition to Coffea arabica are Psychotria nairobiensis and Pavetta elliottii.

(2) Laboratory experiments showed that red berries and large green berries are favoured foods, but feeding will also take place on small green berries, on shoots, and on leaves.

(3) Feeding trials showed that large green berry food is essential for normal length of life and normal egg production.

(4) Antestia was reared to adult stage when fed exclusively on large green berries, on small green berries, and on shoots, but not on red berries or leaves.

(5) In large green berries and small green berries the endosperm becomes infected with rots, usually caused by the fungi Nematospora coryli or Nematospora gossypii, which are introduced by Antestia, but in the case of ripe red berries the endocarp is seldom if ever pierced and rotting of the endosperm is not initiated at this stage.

(6) The amount of damage caused to the crop by rotting of the beans is related to the number of Antestia present, and a formula which is considered to represent this relationship is given. In practice as high a proportion as 97 per cent. of the beans have been found rotted when Antestia is numerous. The figures also show that even when Antestia population is low, an economically important amount of damage to the crop may occur.

(7) Antestia was proved to cause a dropping of young green berries. This seems not to be due to the insect feeding on the stalk, but to be a response by the plant to an interruption of normal growth of the bean due to insect feeding. A similar shedding has been noticed of berries damaged by other insects when it is known that no feeding on the stalk can have taken place.

(8) Feeding experiments in cages and sleeves showed that Antestia must rank as one of the important causes of the non-setting of flowers ; this form of damage has been neglected or minimised in the past.

(9) As a result of Antestia feeding on the growing point, leaves become scarred and distorted.

(10) A useful form of cage for experimental work of this kind is described.

(11) Definite confirmation was obtained that well-known abnormalities of the vegetative growth characterised by multiple branching are produced by the feeding of Antestia.

(12) It is shown that the growth is stopped or much reduced by the feeding of Antestia, and when this is associated, as it usually is, with multiple branching, a “ bunchy ” or “ matted ” growth results, which increases pruning costs and much reduces the cropping ability of the tree.

(13) A short discussion follows which indicates certain practical conclusions that can be drawn from the above results.

Dr. R. H. Le Pelley has reared in Nairobi a number of specimens of a new Tachinid from the diamond-back moth (Plutella maculipennis, Curt.).

Cadurcia plutellae, sp. n : ♂♀.

♂. Head black, the pollinosity of the face, lower half of the parafrontalia and lower half of the posterior orbits inconspicuous, but appearing almost silver-white in certain directions. Eyes bare. Frons one-fifth to one-sixth head-width (slightly less than one-half eye-width) above middle, very slightly dilated to vertex, moderately dilated to lunula ; face moderately dilated with the sides almost straight to the lower margins of the eyes, which are separated by half the head-width ; parafrontalia and interfrontalia somewhat narrowed to about middle, parallel-sided from there to base, the interfrontalia velvety blackish-brown, somewhat wider than the parafrontalia, the latter with about six inclinate and two reclinate setae, the parafacialia with 3–4 descending inclinate frontals, which reach the level of the apex of the second antennal joint. Antennae fuscous-black, third joint more than twice as long aswide, almost reaching level of lower eye-margins, falling short of mouth-margin by half its width, arista minutely pubescent, the hairs shorter than its basal diameter, the basal fourth moderately incrassate. Parafacialia one-half, jowls fully as wide as the third antennal joint, vibrissae level with mouth-margin. Palpi fuscous, hardly projecting beyond mouth-margin.

1. Work on the mosquitos frequenting native huts was carried out at Kisumu, Nyanza Province, Kenya, during 1940–41.

2. During preliminary night and day catches in native huts the catching methods were standardised. Subsequently four identical huts were built side by side for comparative work. They were designed specially for easy catching and had hessian ceilings. Apart from catches made for special purposes, 6 day catches and 1 night catch were made every week in one of the huts for an entire year. This hut was regarded as a control. Records of climate were kept in this control hut for a year, the readings being compared with readings taken in a Stevenson screen outside.

3. It was found that the temperature range in the hut was only about half that in the screen—in other words, a native hut is a very well insulated structure. In hot, dry weather there were considerable differences between indoor and outdoor temperatures but in cool wet weather the differences were very small. Thermograph records showed that the form of the daily temperature curve in wet weather was quite different from that in dry weather. Temperature in the hut very rarely fell below the level at which development of the malaria parasite in the mosquito is arrested. In the screen it very frequently did so in the hours before dawn.

4. Hygrograph records of relative humidity in the hut and screen showed much the same characteristics as the temperature readings. Again the range in the hut was much smaller than that in the screen and differences between indoor and screen humidities were great in dry weather and small in wet weather. The form of the daily curve in dry weather differed markedly from the wet weather curve. Saturation deficit at night was always greater in the hut than outside.

5. At night, the climate of a hut containing 10 natives was compared with that of the control hut, containing 1 native. It was found that the crowded hut was slightly warmer than the other and that its relative humidity was somewhat lower than that of the control hut.

6. High wind at night was unusual. When it occurred the entry of mosquitos to huts was stopped for the time being.

7. A list of all species encountered is given, with locality records and sites of capture.

8. From the results of night catches the entry curves of various species were worked out. It was found that in the case of A. gambiae females there is a high population of resting mosquitos at 7 p.m., a period of low entry from 8 to 10 p.m., a period of high entry from 11 p.m. to 5 a.m., and a sharp entry peak at 6 a.m., due to the arrival of females seeking shelter for the day. The same remarks apply to A. funestus females, but the time distribution of the entry periods is different, namely :—7 p.m., a high population of resting mosquitos ; 8 p.m.–2 a.m., a long period of low entry ; 3–5 a.m., a short period of high entry ; 6 a.m., a large entry of females seeking shelter. In the case of both species, most of the females taken were fed, and there is close correlation between the curves for fed and total females. It is thought that females remain in the hut after feeding. Mature females with Group V ovaries enter mainly at dawn. Males of both species are scarce during the night but enter in large numbers at 6 a.m. to rest during the day. A. coustani and A. pharoensis are scarce in the evening and at dawn. A. coustani shows a well defined entry peak from 11 p.m. till midnight and A. pharoensis from midnight till 2 a.m. T. africanus and T. uniformis act rather similarly. T. uniformis shows a very distinct entry peak at 9 p.m. and T. africanus from 9 to 11 p.m. There is close correlation in this case between unfed and total females. It is thought that these species leave the hut soon after biting and that their biting activity is at a maximum between 9 and 11 p.m. Thus the entry curves of the important species show a succession of entry peaks through the night—T. uniformis, 9 p.m. ; T. africanus, 9–11 p.m. ; A. coustani, 11–12 p.m. ; A. pharoensis, 12 p.m.–2 a.m. ; A. gambiae, 11 p.m.–6 a.m. ; A. funestus, 3–6 a.m.

9. Night catches, comparing dark and dimly lighted tents, showed that A. coustani entered tents in large numbers and preferred the lighted tent, as did T. africanus and T. uniformis. C. nebulosus preferred the dark tent. Catches made in the open showed that A. gambiae and A. funestus prefer to bite in huts, T. africanus and T. uniformis in the open.

10. Comparison of night and day catches showed that the mosquitos taken may be divided into 4 groups :—

1. True house-haunting species, A. gambiae and A. funestus. Females are abundant both by night and by day, males by day only. These species enter both for food and for shelter. Day catches, which included both males and females, give the best estimate of prevalence.

2. Species which enter mainly to feed, T. africanus and T. uniformis ; perhaps A. coustani and A. pharoensis. Females are common by night but are never numerous by day. Males are always scarce. Night catches are essential for an understanding of this group.

3. Species which enter human habitations mainly for shelter, C. antennatus. Females are prevalent by day only.

4. Species which enter casually and are scarce both by night and by day.

11. Analysis of day catches showed that the great majority of A. gambiae and A. funestus females had Grade 1 wings. Sometimes the wings were still undamaged when the ovary was maturing for the second time. Ovary dissections of these species showed that the largest numbers belonged to Group I and that the percentage in this group became higher at times of increase. Most females of these species and of T. africanus and T. uniformis contained blood. Of the unfed A. gambiae and A. funestus, the great majority had Group I ovaries, i.e., they were young females which had never yet fed.

12. Analysis of an A. gambiae increase (December 1940–January 1941) by ovary dissection of day catches showed that the whole increase was dependent on a constant supply of young females with Group I ovaries. As soon as this supply diminished the increase came to an end. It seems, therefore, that the life of the female was short at that season. The numbers of males and females taken were closely correlated throughout.

13. In day catches the great majority of Anophelines were taken on the ceiling. Taeniorhynchus spp. were commonest on the walls. Very few mosquitos were found on the floor. With regard to mosquitos taken on the walls, it was found that all species preferred the lower and darker half. Catches made on the outside of the walls consisted mainly of male Anophelines.

14. In comparative series of catches made to determine the best hour for day catching, no significant difference was found between catches made at all hours from 6 to 11 a.m.

15. Preliminary tests showed that there was probably a quantitative relationship between the numbers of human inhabitants of a hut and the numbers of mosquitos taken. This was confirmed by night and day catches made simultaneously in huts with 1, 5, 10 and 15 inhabitants respectively. It was found that there was a very close direct relationship between the size of the human population and the numbers of females of biting species taken. Non-biting species did not discriminate between the huts.

16. Comparison was made between huts containing 5 washed and 5 unwashed natives respectively. All the important biting species preferred the hut with the unwashed natives.

17. In night catches, A. gambiae and A. funestus females preferred a hut containing dirty clothing only to a completely empty hut. Females of T. africanus and T. uniformis showed no such preference.

18. Catches in empty huts showed a relative but not an absolute increase in Anopheline males.

19. It was found that a hut subdivided by a hessian curtain could be used for preference experiments with varying human population.

20. In a comparison between a hut containing a native and one containing a calf, it was found that A. gambiae and A. funestus were more numerous in the hut with the native both by day and by night. A. funestus showed a more marked preference for the native than did A. gambiae. A. coustani, A. pharoensis and C. antennatus showed a distinct preference for the calf. In the hut with the native, Anophelines formed 94 per cent. of the total catch, but in the calf hut Culicines formed 95 per cent. of the total.

21. It is shown that at Kisumu the seasonal incidence of A. gambiae is dependent on local rainfall. The relationship is qualitative rather than quantitative. A threshold figure of 5 inches of rain per month is necessary before an increase can take place. When an increase does occur, the population in the first month of the increase is proportional not to the amount of rain which has fallen but to the lower initial population of the preceding month. If the increase is maintained for several months, the growth of the population takes place in geometrical ratio.

22. At Kisumu the seasonal incidence of A. funestus is not connected with local rainfall. Increases take place when the level of Victoria Nyanza rises. The rise in lake level is dependent on the rainfall of a large part of East Africa and is independent of local rainfall.

23. The seasonal incidence of other species is briefly discussed.

24. The parasites noted from mosquitos were mites, which were most prevalent on A. coustani and A. gambiae, and Coelomomyces africanus which was commonest in A. funestus. Coelomomyces is a fungous parasite which causes destruction of the ovaries. It is now recorded from Kenya for the first time. Unsuccessful attempts were made to infect larvae with this fungus, but naturally infected larvae were found.

25. Unsuccessful attempts were made to render adult mosquitos individually recognisable by staining the larvae with various dyes. Attempts to make the blood-meal recognisable by injecting identifiable substances into the blood-stream of the human bait were also failures.

Since 1930 the European spruce sawfly (Diprion polytomum) has caused severe damage in eastern Canada and is a meance to the spruce woodlands in the northeastern part of the United States. In 1938 under a cooperative arrangement with the Division of Entomology, Canadian Department of Agriculture, and the Farnham House Laboratory, Imperial Institute of Entomology, England, which were to continue their collecting in the central European area for the recovery of natural enemies, the Bureau of Entomology and Plant Quarantine, United States Department of Agriculture, made a survey of the Scandinavian and eastern Baltic countries to extend the knowledge of the distribution of the sawfly ; to discover, if possible, better or equally as good collecting grounds, where new species of parasites might be found ; and to obtain additional information regarding the better known species of parasites. The most favourable habitats of the sawfly are found in the one-generation areas under conditions which provided a maximum of sun-heat, moisture, and shelter, near to the upper limits of spruce growth. The least favourable habitats are the drier, less humid places, especially in the two-generation areas. The sawfly was found everywhere on spruce, from the German-Danish border in Denmark and in southern Norway to the northernmost spruce forests of Sweden, and from far above the Arctic Circle in Finland southward through the eastern Baltic countries of Estonia, Latvia and Lithuania. The range of distribution covered in this survey was from approximately latitude 55° in Denmark and Lithuania to latitude 68° 45′ in Finland. This includes most of the Scandinavian Peninsula, Fennoskandia, and the eastern Baltic countries. Spruce comprised from 25 to 40 per cent. of the productive forest land of this large area. Large collections of the European spruce sawfly were made in Sweden and Finland for the Canadian Division of Entomology.

Linnaeus (1746) described a black aphis which he found on Rumex sp. and called it Aphis rumicis. Fabricius (1794) described a black aphis “ Aphis rumicis,” found “in Rumice acuto” and mentioned pale antennae and tibiae. Risso (1826) recorded a species, Doralis rumicis, Leach, found in the Mediterranean region, but did not describe it. Koch (1857) recorded Aphis rumicis, L., from Rumex crispus, feeding chiefly on the stems and flower-stalks. This aphis is also frequently found on thistles and beans. The apterous female has black antennae, white only at the base of the long “ fourth joint.” The wing-pads and thorax of the alate nymphs are olive-green. Kaltenbach (1874) described black Aphids developing from eggs on dock, and having a second winged generation which settles on beans, thistles, Chenopodium sp., and other plants. He observed that the Aphid colonies are on the leaves and flower-stalks. Buckton (1879) gave an illustrated account of a black aphis, Aphis rumicis, L., which has a large number of food-plants including Rumex crispus, Carduus lanceolalus, and broad bean, with furze as its winter host. He noticed the presence of large white flecks on the “pupae.”

1. When spring migrants of Aphis fabae, Scop., from Euonymus europaeus and Viburnum opulus are given a choice of summer host plants enclosed by a muslin cage, they colonise bean first and then sugar beet. Dock, poppy and Chenopodium are colonised in no very definite order, but thistle is the last plant to be infested.

2. Further infestation of surrounding plants takes place rapidly by means of apterae, which migrate actively and colonise plants at random.

3. The total number of Aphids on the summer host plants is of the same order as the times of colonisation.

4. The effect of parasites and predators is proportional to the numbers present and to the size of the colony.

5. The results do not indicate the presence of biological races on the chosen host plants.

I should like to thank Mr. F. G. W. Jones, of the School of Agriculture, Cambridge, for his help in preparing the ground for the plots and in rearing some of the plants, and Dr. W. H. Thorpe for his criticism.

The larvae of the three common species of Ephestia, E. kühniella, Zell., E. elutella, Hb., and E. cautella, Wik. , are serious pests of stored food products, particularly cereals, dried fruits, nuts, and cacao. These species often occur together on stored foods, e.g., E. elutella and E. cautellaon dried fruit, or E. kühniella and E. elutellaon grain. Sometimes all three are found together on the same product. To know what species are present is of considerable importance, since they differ in the amount of damage they are likely to do, in their resistance to fumigants, in the frequency with which they are recorded as pests of Other products, etc. It has not hitherto been possible to identify the larvae with certainty except by breeding them out, which is unsatisfactory, both because of the time it takes and because it frequently happens that many of the larvae confined in breeding cages die of “wilt.”

Outbreaks of yellow fever in the Anglo-Egyptian Sudan and Uganda in 1940 emphasised the necessity for the mosquito control measures which are in force to prevent the disease from reaching Egypt or the East African ports. Edwards (1941, Mosquitoes of the Ethiopian Region, III, p. 3), referring to yellow fever, states that “ it would seem that most of the common biting mosquitoes of West Africa are to be regarded as potentially dangerous.” This statement applies also to north-east Africa. For the further planning of control measures, more information is required as to which mosquitos can act as vectors. Transmission experiments can usually be carried out only in a few specially equipped laboratories, so that mosquitos must sometimes be transported over great distances. A convenient method of doing this is to carry several thousands of living larvae which can provide a supply of adults for experiments. The writer has, for several years, used the simple method described below and found it effective in the hot dry climate of the northern Sudan. Recently it proved useful for sending larvae of species of Aëdes to the Yellow Fever Reseaich Institute at Entebbe.

Larvae are stranded on a wet surface in a cool damp atmosphere and can be carried under these conditions for many hours or even several days. Perforated trays are made from the metal of petrol tins as shown in Fig. 1. A piece of cloth 44 cm. square is laid over each tray and tied underneath it. Water containing the larvae is poured into the tray and drains away, leaving the larvae stranded. A metal cross-piece laid on the tray serves to support another tray above it. Eight trays can be placed in a four gallon petrol tin which is then closed with a lid. In hot weather a wet towel may be wrapped round the tin.

The genus Podagrica occurs in very large numbers in Africa, both as regards species and specimens, and from the records we already have, at least twelve are recorded as doing damage to cotton, Hibiscus and other plants. A list of these is given and also a list of described African species, there being at present no up-to-date catalogue of the Halticinae.

Weise, in Naturgeschichte der Insecten Deutschlands, 26, 1886, p. 681, sinks the genus Nisotra, Baly, 1864, to Podagrica, Foudras, 1860, quite rightly. There are already 39 described African species, to which I now add eight new ones. There can be no doubt that the whole genus will prove to be destructive to various crops. It ranges from Europe to Australia, but does not occur in North or South America. The species are very difficult to define, almost as much so as the genus Haltica ; the species having the prothorax fulvous and the elytra blue form the largest group ; another group is entirely flavous or fulvous, and a third small group has spots or slight markings.

A lateral view of the terminal segments is essential for the identification of a Culicine larva, but owing to the necessity of the larva to pierce the surface film of the water with the spiracular valves at the distal end of the respiratory siphon, it will retain a position with the dorsal surface uppermost in spite of all efforts to induce it to do otherwise. Even if placed in water so shallow that there is insufficient space between the bottom of the container and the surface of the water for the siphon to be held erect, the insect will incline its siphon but keep the rest of the abdomen dorsum uppermost, thus possibly presenting a lateral view of the siphon, and showing the pecten, but the comb and anal segments will still not be in a suitable position for a detailed study of the characters to be made

In 1939 I dealt with two species of Ephialtes which parasitise the codling moth, Cydia pomonella, L., namely E. caudatus, Ratz., and E. crassiseta, Thoms., and showed how they differed from E. punctulatus, Ratz. (=extensor, Tasch.) with which species they had formerly been confused. During 1940, F. J. Simmonds, of the Imperial Institute of Entomology, sent to the British Museum a series of a species of Ephialtes bred from this same host in the south of France. This is a new species, and it was previously known to me only from a single female which had been bought by D. S. Wilkinson from O. Schmiedeknecht, who had incorrectly named it Pimpla roborator, F. In fact, this new species does not belong to the same species group as Ephialtes (Exeristes) roborator, F., Grav. (=Pimpla roborator, F., Schmied.), which is a well-known parasite of the European Corn Borer (Pyrausta nubilalis, Hb.) and also parasitises many other hosts.

As there has been considerable confusion in the synonymy and interpretation of E. roborator, F., it seems advisable to give notes on the relevant type specimens seen by me. It has been impossible to find the type of Ichneumon roborator, F. Gravenhorst's interpretation of this very variable species has therefore been taken. The description given by Schmiedeknecht in his Opuscula Ichneumonologica is adequate for the recognition of the female ; the male is very distinct, having a tubercle in the middle of the clypeus, a character unknown in any other described European species. Pimpla cicatricosa, Ratz., which is given by Schmiedeknecht as a synonym of P. roborator, F., is a distinct species.

The genus Pagria, as will be seen from the following records, contains many injurious species feeding on various species of beans, etc. These have all been forwarded to the Imperial Institute of Entomology from time to time for identification :—

One or two errors in “ Mosquitoes of the Ethiopian Region ” have recently come to light, and several new Culicine larvae have been discovered since the first volume was published. I take this opportunity to correct the errors and to indicate the positions which the newly-described larvae should occupy in the keys. I have not seen most of these larvae and have inserted them in the keys solely from the descriptions.

A number of the mosquitos of which I described the larvae in Vol. I of the monograph were incorrectly determined, but Edwards has already pointed out these misdeterminations (in Vol. III) and I have not thought it necessary to mention them here.

At the request of Mrs. G. R. Cunningham van Someren (formerly Miss E. C. C. Macdonald), I have added her description and figure of the larva of Aëdes adersi and her description of that of Culex adersianus as an appendix (see p. 178).

Nine samples of waste oils have been examined and after blending with kerosene and Diesel oil their suitability as larvicides was determined. It is concluded that blends containing 25–30 per cent. of waste oil are not so effective as an approved commercial larvicide at the same dosage but that with a higher dosage, which is still within the range commonly applied in the field, i.e. between 4 fl. oz. and 6·7 fl. oz. per 100 sq. ft. (Ramsay & Carpenter, 1932) they give good results. The higher dosage is only necessary when Culicine larvae have to be controlled. Other blends containing 10–20 per cent. of waste oil are just as effective as an approved commercial sample.