In several previously published papers dealing with African Diptera I have described a number of species belonging to the genus Sturmia, Desvoidy, but up to the present time have not had sufficient material available to warrant the preparation of a key to the species, nor have I had an opportunity of studying the species in sufficient detail to decide upon characters of value in their classification. However, since many species were reared and it was desirable to have names for them in order that they might be used in reports by various Entomologists in Africa, a number of the species were described, and it has since been possible to make considerable progress in the study of the whole. As a result a key to the species belonging to this genus is now presented, and it is hoped that it will be of assistance in identifying the representatives of this difficult group.

It is further hoped that arrangements may be made in the near future for the publication of a key to the genera of the Tachinidae, since it is obvious that with the very large number of genera described, the description of an additional genus, or even of new species in old genera, conveys little of the true relationships of the forms described and merely adds to the difficulty of making determinations.

There are three main parasitoids and one very efficient predator associated with Perrisia pyri in France. Of these, at least during July and August, the predacious Capsid, Pilophorus perplexus, achieves the greatest destruction of midge larvae.

The two species of Platygasterids differ in several points of ethology from the species of the same or adjacent genera attacking Contarinia pyrivora. They are both egg-parasites, developing very slowly in the midge larvae during the growth of the host. Their action appears to be largely complementary, corresponding to morphological differences in the organs of oviposition. Their life-history is very imperfectly known.

Torymus abbreviatus is extremely efficient. Its eggs are laid within the curled leaf among well-grown midge maggots on which the larva lives as an ectoparasitoid. The duration and location of the pupa stadium is unfortunately not yet known.

Some half a dozen other enemies were found to play a less important part than the preceding.

(1) During studies on the mosquito breeding occurring in tree-holes in the vicinity of Lagos, Nigeria, water was collected from holes in 260 trees. This number included 36 species, consisting largely of fruit trees and those used for shade and ornamental purposes.

(2) Mosquito larvae were present in samples of water taken from 227, or 87·3 per cent., of the trees.

(3) The number of adult mosquitos bred out from all larvae collected totalled 12,285, with 14 species represented.

(4) Among the several species, Aëdes aegypti stood second in the number of trees in which it was found and fourth in the number of adults bred out.

(5) Aëdes aegypti larvae were taken from holes in trees at a distance of 350 yards from the nearest habitation.

(6) The amount of breeding of Aëdes aegypti found occurring in tree-holes was sufficient to demonstrate their importance as a source of mosquitos of this species and the necessity for their elimination as a measure in yellow fever control.

During the past few months the writer conducted observations to determine, first, if Aëdes aegypti preferred places of oviposition within habitations or those located outside with natural shelter near by, and, second, the distance from human habitations at which this species may breed. These investigations were carried out in, or near, the compound of the West African Yellow Fever Commission at Yaba, near Lagos, Nigeria.

The specimens which form the basis of the following notes and descriptions were received by the writer from Mr. T. H. Colebrook Taylor, Assistant Entomologist, Fiji Islands, and were reared by him in the course of investigations looking to the introduction into the Fijis of parasites of Coccidae for the purpose of controlling the scale pests of coconut. One genus, two species and a variety are described as new.

The importance of the reaction of mosquito breeding water was established by MacGregor in 1921, and since then observations have been reported from various parts of the world. In the original paper MacGregor showed that, in the laboratory, three species of English mosquitos could survive an alkalinity of pH 9·6 and died in acid water of pH 4·4, while two other species developed in pH 4·4. Later, in Mauritius, he found the local Anophelines in water ranging from pH 9·5 to pH 8·4 and rarely in places giving the reading pH 7·4 ; and maintained that the reaction of any water there was a reliable index of the presence of Anopheline larvae. Senior White, in Ceylon, found the local Anophelines in water with readings from pH 5·8 to pH 8·6 usually, and decided that on the whole the local Culicines had a more restricted range. Buxton, in Palestine, found six species of Anopheles in water varying from pH 9·2 to pH 7·4, and of these only one occurred in water less alkaline than pH 8. He notes that Nablus, where the water supply is unusually acid for Palestine (pH 7 to 7·5), is free from malaria.

From the above it will be seen that in the writers' opinion, based it must be admitted on but a single year's observations, the three species of Dysdercus (D. fasciatus, D. nigrofasciatus and D. superstitiosus) occurring in the northern rain-cotton belt of the Sudan are essentially associates of the tebeldi and are not as yet other than accidental pests of cotton. By this is meant that there is no definite migration from the tebeldi to cotton, nor are wandering adults greatly attracted by cotton. The dispersal of a proportion of the adults composing a colony on a tebeldi is the natural effort on the part of the species to establish itself on other tebeldis. Emigrants from a colony that in the course of their wanderings chance on cotton may remain to breed. It is possible that when cotton has been grown in the district on a large scale for some years, the bugs, unless they are kept in check, may develop the habit of migrating definitely from the tebeldis to the cotton and, later in the season, from the cotton back to the tebeldis.

The most promising line of attack appears to be that of destroying, so far as possible, the colonies on the tebeldis during the active breeding season.

The writers' thanks are due in particular to Mr. G. F. March, Inspector of Agriculture, who in a variety of ways has rendered them the greatest assistance in their work.

The Tachinidae described herewith have been forwarded for determination through Dr. Guy A. K. Marshall, Director of the Imperial Bureau of Entomology, and constitute three of five species reared by Mr. E. Ballard. The types of the new species will be found in the British Museum of Natural History.

The two new species described below were included in collections sent to the Imperial Bureau of Entomology by Dr. P. A. Buxton, of the London School of Tropical Medicine, having been obtained in Kashmir by Major Stevenson in 1926, and again in 1927. The same collections contain examples of a third species of Simulium which appears indistinguishable from the European S. equinum (L.) Edw. Examples of this species had previously been obtained in Kashmir by Mr. F. J. Mitchell.

♂. Black ; flagellum brownish red, hind legs from the femora to the claws blackish red ; scape, fore and middle legs, hind trochanters and hind trochantines, light testaceous red ; palpi almost white ; basal ventrites whitish ; stigma and wing veins brown.

♂. Head rugose throughout, except that the occiput is rugoso-reticulate and that the vertex between the ocelli and the toruli is rugoso-striate ; face with indications of a median keel ; antennae moderately thick and strong ; basal joint of flagellum a little longer than twice its breadth, about 0·24 mm. long ; clypeus apparently emarginate, just about half as long as distance between facial depressions, which latter are nearer to the eyes than to the apex of the clypeus ; posterior ocelli nearer to the eyes than to each other. Thorax : mesonotum closely and strongly punctate, anteriorly almost rugose, as are also the mesopleurae except for a posterior median smooth and shining area ; mesopleural sulcus apparently smooth ; scutellum apparently rugose ; metanotum apparently not crenulate ; propodeon with an extremely short median longitudinal carina which, bifurcating at its apex, emits two strong carinae which, on each side, run transversely across the basal half of the propodeon and join a strong carina which in conjunction with a strong lateral longitudinal carina encircles the spiracles, as in M. kuchingensis ; remainder of the propodeon apparently rugose between broad reticulations, except outside the lateral keels, where it is only rugose.

During recent years a great deal of research work has been carried out in connection with the control of the black currant gall mite Eriophyes ribis (Westw.) Nal. This work has necessarily included the very careful study of the mites themselves, in order that the life-cycle might be fully understood, with the final object of trying to exterminate the mites at a period when they offered least resistance and were not living within the buds, which afford them adequate protection.

While examining some black currant bushes in the late spring and summer months of 1923, in order to locate the position and determine the habits of the mites during that season, a rather peculiar form of mite was noticed to be present in small numbers. This new mite, when examined in the field, appeared to be very much stouter and of a darker colour than the familiar black currant gall mite. However, for some time it was regarded as being an immature stage of the common species. After some months this mite turned up again in greater numbers, and it was decided to examine it in detail in the Laboratory. The species proved to be a new one belonging to the genus Phyllocoptes.

The pineapple is a plant indigenous to Central America and, it is believed, Trinidad also. In this part of the world its cultivation has developed on commercial lines only in Cuba and Porto Rico, and to a lesser extent in Jamaica, with small areas in other islands, particularly Martinique.

There have been of late indications of an increased interest in the possibilities of fruit production on a large scale in Trinidad, the pineapple being among the favoured fruits. For this reason the pest dealt with below assumes a greater importance than it otherwise would, though the usual freedom of this plant from pests focuses attention on any new one found.

In October 1926, young fruit on the plots of the St. Augustine Experiment Station of the local Department of Agriculture were found to be exuding gum and showing signs of insect attack. Though at the time there was few fruits, it being too early for the main crop, a high proportion of these was found to be damaged. It was reported that many fruits had been rendered unsaleable during the previous season by a similar attack.

[In 1919 work on the genus Oneilella was begun by the author and Mr. R. E. Turner. General agreement was reached as to the species represented in the material studied, and a table constructed before Mr. Turner's return to S. Africa. Subsequently all the additional material now dealt with was seen by Mr. Turner, and determined in collaboration.]

The genus Oneilella, Cam. 1904, created for the reception of Cryptus formosus, Brullé 1846, has up to the present remained monotypic. That it contained many more species was evident after an examination of the examples of this genus available in the British Museum collection and in various collections forwarded for identification to the Museum or received through the Imperial Bureau of Entomology. The material so gathered together (over 450 specimens) is, with one doubtful exception, African in source and dates from 1848 onwards. Its analysis has been a matter of some difficulty and has been undertaken chiefly because of the economic importance of some of the species. In the following pages an attempt has been made to summarise our present knowledge of the genus and its parasitism, and to describe such forms as appeared to be new.

In the Revista Industrial y Agrícola de Tucumán of November 1923 to January 1924, 4th year, numbers 6–8, Arthur H. Rosenfeld & T. C. Barber published an interesting article on the sugar-cane moth borer, known in Tucumán as the “ gusano chupador de la caña de azucar,” in which they detail the different effects of the said moth borer (Diatraea saccharalis).

Last year, Dr. William E. Cross, Director of the Estación Industrial y Agrícola de Tucumán, was good enough to entrust me with the study of some Diatraea parasites, the identification of which had, so far, only been effected generically.

My best thanks are due to Dr. Cross for having supplied me with material for this investigation, which I consider very interesting, owing to the daily increasing importance of the biological control of agricultural pests.

There is no doubt but that by continuing these investigations other parasites will be discovered ; this is as yet only the first step on the road which may lead to very important results.