Although it may be convenient to distinguish them, hibernation, aestivation, and diapause are in reality different manifestations of the same phenomenon which we may call diapause. The symptoms of this condition are a marked depression of metabolism and quiescence; and the remote causes as suggested by observation are cold, heat, drought and (or) certain nutritional peculiarities such as richness or dryness of food. These factors may act singly or in combination, with different factors dominant in different cases.

On 25th August 1914, the medical officer in charge of a rubber estate in Malaya wrote to the manager a report about a new method of polluting Anopheline breeding-places: “It will interest your Directors to learn that by oiling with the mixture in use on Sungei Way, one of the ravines in the West Divisions has been kept free from Anopheles for several months. Formerly they bred freely in it. I am encouraged to think that this is not merely due to the physical difficulty the larvae would have of getting air when oil is on the water, but that some change has actually taken place in the water as a consequence of the oil, and a change which would make it uncongenial to the stream-breeding mosquito. My reason for thinking this is that in the bottom of the ravine a green slime has developed, in the presence of which I have never found dangerous anophelines” (Watson, M. 1921). Before 1914 oil had been used on standing water, and poisons had been used in running water (Howard, Dyar & Knab, 1912) to reduce the breeding of mosquitoes. But this discovery, that it could be effectively and economically used even on fast-flowing streams to control Anopheles, made the use of oil par excellence the great standby in emergencies of malaria; while it may be the method of choice if control measures are only required for two or three months in each year.

The grain weevils of the genus Calandra, F., are more strongly represented in the Oriental Region than in any other part of the world. In addition to the eight Indian species dealt with in the following key, four others have been recorded from further east, and some ten additional undescribed species are known to me, mostly from the Malayan Subregion.

1. From the study of the historical records of European invasions by Locusta from the 14th century to the present day, it is concluded that the subspecies concerned was L. m. migratoria originating in the West Pontian outbreak area. This area formerly comprised the lower courses of rivers draining into the Black Sea from the Danube to the Dniepr inclusive, and is now confined to the delta of the Danube. From here swarms migrated into central Europe and the eastern part of the north European plain. The northern part of the plain, the British Isles and Fenno-Scandia, lie on the outskirts of the invasion area, and as a rule were only reached by small detachments from swarms. The decline of the West Pontian outbreak centres was accompanied by the gradual decline of the area subject to invasions by large swarms, but during outbreaks small groups and separate individuals of ph. gregaria continue to reach the further limits of the invasion area.

2. The distances covered within a single generation by swarms of L. m. migratoria in temperate Europe (up to 1,600 miles) were comparable in extent to those traversed by L. m. migratorioides in tropical Africa.

3. Long-range migrations to the extreme limits of the invasion area are not confined to L. m. migratoria ph. gregaria but occur also in ph. solitaria. This is shown by the arrival of individuals of this phase in the British Isles during theperiod when the West Pontian outbreak areas are in a quiescent state. From this and from literature data on other locust species it is concluded that long-range migration is a regular seasonal phenomenon in swarming acrididae, independent of the presence of large numbers or the phase.

4. The late summer immigration of L. m. migratoria into the British Isles may be a part of a more general east to west movement of flying insects which may occur in Europe at that season.

5. It is probable that L. m. migratoria sometimes oviposit in the British Isles, for they may arrive in a mature state, or during exceptionally hot summers in southeastern England they may reach sexual maturity after arrival. The eggs, however, are apparently unable to survive winter conditions.

In 1927, 1931, 1935 and 1937 the writer published four papers on the food-plants of Nigerian insects in this Bulletin (18, pt. 1; 22, pt. 2; 26, pt. 2; and 28, pt. 1). The present paper contains additional data obtained between April 1936 and October 1939.

The work which has resulted in the following paper has been carried out in the Department of Entomology of the British Museum (Natural History), at the request of Professor J. W. Munro and on behalf of the Pest Infestation Laboratory of the Department of Scientific and Industrial Research. The critical material used has been mainly that already available in the British Museum, but it has been partly supplemented from Professor Munro's resources.

Twenty-three species of Metaphycus from Africa are recognized in this paper, and of these, seventeen are described as new. The holotypes and allotypes of all new species are to be deposited in the British Museum and paratypes in the United States National Museum.

During the last twenty years, the Forestry Commission, several local authorities, and a large number of private woodland owners, have expended a total of several million pounds in an endeavour to replace the stocks of growing timber which were so heavily depleted during the last war. Several hundred thousand acres have been planted and a large proportion of these areas have been stocked with coniferous species.

1. Melittomma insulare is a serious pest of coconuts in parts of Seychelles and Madagascar.

2. In Seychelles the insect is only known from a few of the islands, its distributio being dependent on the original distribution of its primitive host-plants which are two species of endemic palms.

3. The eggs are laid under cover in batches and hatch in eleven days. The larvae feed in galleries in the base of the trunk for an indefinite period depending on the sappiness of the wood. Pupation takes place in the enlarged end of a boring. The adult is nocturnal and short-lived.

4. The damage caused depends on the age and situation of the tree which is attacked. Other things being equal trees growing on good soils are damaged least.

5. Several other species of insects are associated with Melittomma, but all are of minor importance.

1. The investigation which forms the subject of this paper was commenced in 1936 and closed in 1939. Owing to the low returns from an acre of coconut land it was imperative that control measures should be cheap. Biological methods were therefore employed.

2. The soils on which coconuts are planted in Seychelles fall into three main types: (a) beds of coral sand, (b) various types of transported soils, (c) sedentary soils.

3. The robustness of the trees was found to be in direct proportion to the quality of the soil. The best trees are located on the deeper alluviums. The limiting factor on the coral sands is often drainage. On the hill-sides the trees deteriorate in proportion to the soil impoverishment and erosion.

4. A complex of scale species attack coconuts in Seychelles. None of these presents major problems in other countries, and the better known scales which are pests on this crop in other countries are not found in Seychelles. Four major species are mentioned, two of which are recent introductions to the islands. The life-history and particular requirements of each species are given and their incidence on coconut and their interspecific relationships are discussed.

5. In order to combat these scales four species of Coccinellidae were introduced from East Africa, two of which were predators on Diaspid and two on Lecaniid scales. The life-history, breeding technique and establishment of each is described.

1. Eight Ichneumonoidea, fourteen Chalcidoidea and six Proctotrupoidea are recorded as parasites of willow insects.

2. The majority of records are of parasites bred from insects inhabiting the wood of the cricket bat willow, Salix alba var. caerulea, Smith, the more important being Torymus pulchellus, Thoms., Tridymus salicis, Nees, Eupelmus urozonus, Dalm., Microterys clavellatus, Dalm., Tetrastichus roesellae, DeG., Tetrastichus inunctus, Nees, Tetrastichus flavovarius, Nees, Tetrastichus ? acuminatus, Ratz., and Platygaster sp.

3. Microterys clavellatus is recorded for the first time as a parasite of Cecidomyiidae.

4. Evidence is given for the separation of the gall-midges, Rhabdophaga sp. and R. saliciperda, Duf., as distinct species based both on structural differences and on a study of their parasites, for the three parasites found most commonly attacking Rhabdophaga sp. were never bred from R. saliciperda, and the most common species parasitizing R. saliciperda was never obtained from Rhabdophaga sp.

5. It is confirmed that Eurytoma salicis, Thoms., supplements its animal diet with vegetable food.

6. The rate of parasitism of Euura atra, Jur., by Eurytoma salicis is given as 19·8 per cent., and that of Rhabdophaga sp. by Platygaster sp. as 40·5 per cent.

7. Histograms are given of Rhabdophaga sp. and its parasites, Torymus pulchellus, Thoms., Tetrastichus roesellae, DeG., and Platygaster sp., the emergence of Platygaster sp. coinciding approximately with that of its host.

The Institute of Plant Diseases at Buitenzorg has been engaged in the study of the well-known coconut pest, Artona catoxantha, Hamps., and has sent to the Imperial Institute of Entomology a large and very interesting collection of its parasites and hyperparasites. We understand that Dr. J. v. d. Vecht is preparing a paper on the ecology of this Zygaenid. To complete his studies on the life-histories of all these parasites we have been asked to make a special study of the Chalcids.

At least 30 specimens of each form of Macrosiphum rubiellum, Theobald, and Aphis idaei, van der Goot, were collected, mounted and their principal organs measured.

Correlations were calculated between different parts on the right side and the conclusion reached that the ratios of lengths of organs were unstable characteristics of the species examined. High correlations were obtained between the same part on different sides of the body.

The mean values and standard errors are tabulated and a method given for assigning limits of variation within a species. The standard errors obtained were of the order of 7 per cent. of the mean.

The asymmetry, kurtosis and skewness of the distributions were calculated to test the effect of possible non-normality on the foregoing work.

In Vol. 29 (March, 1938) of this journal a short summary was given of the results achieved during an investigation of the wood-destroying insects in public buildings in the southern part of Sweden, Götaland. This survey has since that time been continued in Svealand, the middle part of Sweden, and in the following a short summary of the results will be given.

The information contained in this paper was prepared by me originally for inclusion in my forthcoming monograph on the palaearctic species of A panteles, but, in view of the economic importance of the hosts of this particular species, it was deemed advisable to publish it immediately.

♂♀. Derm black, with dense sandy grey scaling, the elytra with a small brown spot at the base of the suture and often some indefinite brownish markings elsewhere; underside grey.

The research work involved in this paper was financed by Messrs. Levers Pacific Plantations Pty., Ltd., of Sydney, and I wish to acknowledge the help and courtesy extended to me by so many members of their staff.

During his researches on the insect pests of coffee and their parasites in Kenya Colony, Mr. R. H. LePelley has bred two interesting Chalcidoidea from the eggs of the coffee-bug, Antestia lineaticollis, Stål.

In a previous paper (Leeson 1937) it was shown that in East Africa there were variations in the wing markings of the type form of Anopheles funestus. It was further shown that larvae and pupae positively identified as typical A. funestus produced adults having these wing markings. Identification of the adults was confirmed by examination of pharyngeal armatures and male terminalia. The wing forms were then arranged in the following four groups:— Group 1: dark area at base of costa uninterrupted, 3rd vein with a pale interruption. Group 2: dark area at base of costa uninterrupted, 3rd vein entirely dark. Group 3: dark area at base of costa interrupted by one pale spot, 3rd vein with a pale interruption. Group 4: dark area at base of costa interrupted by one pale spot, 3rd vein entirely dark.

1. G. pallidipes almost invariably attacks man on the leg from the knee downwards.

2. G. brevipalpis may attack man anywhere and not infrequently on the head.

3. Both species fill themselves readily with human blood once an attack has been made.

4. Neither sex of either species attacks man unless very hungry, as indicated by the very low mean fat content in the captures.

5. G. brevipalpis is apparently more reluctant even than pallidipes to attack man, and the fat contents in flies caught on man are proportionally lower than in the case of pallidipes.