This paper reviews recent developments in locust control since 1936 and indicates what, in the writer's opinion, are the most important aspects of the problem requiring further investigation and improvement if fresh advances are to be made.
The Isopteran collection of the late Dr. Claude Fuller consisted largely of vials of unnamed specimens. During the period 1936 to 1938 the writer despatched to Dr. A. E. Emerson all the Hodotermitidae and Kalotermitidae for redetermination of the species identified by Fuller, and for determination of the unnamed material. The following report is based on some of the material determined by Emerson, as well as on a collection made, compared and determined by the writer.
The material and data upon which the following notes are based have been obtained during the last four years in the Eastern Cape Province. In addition to food-plants, life-history data, where these are known, are given.
The diet of the inhabitants of the island of Tristan da Cunha in the South Atlantic, consists principally of potatoes that are grown in walled ""patches"" which provided some shelter from the strong winds. An insect pest, locally known as the"" potato grub"" caused extensive damage to the potato crop. According to Naude (1947) the insect had been identified as Meliana exul. Very little was known about the pest. Members of the recent expedition to Tristan da Cunha did a study but had to limit their activities to testing three insecticides.
A female of Charaxes pelias pelias Cram., the typical Cape race, was noticed on plants of Rafnia amplexicaulis. Larvae were found by looking over Rafnia plants. Detailed descriptionptions were made from the original egg and the resultant larva and pupa, some notes being added on the variation in larvae which were taken in the field.
No representative of the genus Pygothrips Hood has apparently been recorded from South Africa, although P. spinicauda Priesner was descriptionbed from the Belgian Congo. The new species descriptionbed below was found on dry branches near the coast in Zululand.
In an earlier paper an attempt was made to correlate the host-plant preferences of certain groups of Trypetidae with their taxonomy. A suggestion was made of a series of genera from Afreutreta to Oedaspis, the gall-forming habit being, as far as the biology is known, a common characteristic. It has not yet been possible to make a detailed survey of the whole series, and much more biological data is still needed. Much more must also be known of the possibly more basic groups of species in the Tephritine genera Spathulina, Trupanea and others, and among which gall-making often occurs.
Large scale cultivation of turf grasses in South Africa is a comparatively new venture which is besetï¿½ with many problems. The study of its entomological problems shows that many insects, previously considered harmless, have now assumed new roles in that they have become serious pests. A recent example of this concerns a Coccid, which has been reported from golf courses in Natal, and at present seems to be confined to a narrow coastal strip between Mount Edgecombe and Umkomaas.
It is of vital importance, when breeding parasites under laboratory conditions, that wastage of material should be avoided, and that the progeny of both the host and the parasite should be healthy and fertile. Therefore the influence of population densities on development and oviposition should be studied, in order to determine the optimum density for the rearing of any species in large numbers. Population densities are also of great importance where insects are reared in laboratories to test and standardise insecticides.