An extensive survey of the mealybugs attacking vines in the southern districts of the Cape Province, recently arranged by Dr D. P. Annecke of this Institute, showed that the species predominant at vintage time is that currently known as Planococcus ficus (Signoret, 1875). The insect is not new to South Africa, having been first discovered in 1914 by De Charmoy who referred to it as Pseudococcus vitis (Niedielski, 1870). The following year Brain (191.'}), either because he was unaware of that record or because he adopted the views of other authors, listed vitis (and ficus) amongst the synonyms of Pseudococcus citri (Risso, 1813). Thenceforth the name passed to oblivion and the identity of the species was confused with that of the citrus mealybug.
Tensile measurements on beetle and moth larval cuticle indicate that there is a much wider range in the mechanical properties of insect solid cuticles than was previously known and that lepidopterous larval cuticle is associated with plastic deformations far in excess of those for cither beetle larval or other kinds of sclerotized cuticle.
The spider genus Loxosceles Heinecken & Lowe is known to occur in the Americas, Africa and the Mediterranean region. In recent years Loxosceles has featured prominently in scientific literature because of its medical importance. The bite of certain species is known to cause necrotic lesions in man which may vary from mild to very severe. As pain normally only develops some hours after the bite, it has been difficult to incriminate this spider in most cases. In the Americas, loxoscelism was first reported from Chile in 1937 when Macchiavello (1937) demonstrated how the bite of L. laeta (Nicolet) caused severe cutaneous necrosis.
The following descriptionption is based on samples of P. minimus Ruelle from Zaï¿½re and Zambia (see below). Comparisons are made with published data on the genus Macrotermes as revised by Ruelle (1970) and with unpublished data from preliminary studies by the. author on about 230 alate specimens of Allodontermes and Odontotermes.
Although the genus Idiocerus is well known in the Palearctic and Nearctic regions, our knowledge of the Ethiopian species is still very limited. At the present time ten species are included in Idiocerus from this region, seven from Africa and three from Madagascar. The first species to be descriptionbed were haupti and quadriocellatus from Tanzania, by Melichar in 1908. Later he descriptionbed funereus from East Africa (Melichar, 1911) and citrimus from the Belgian Congo (Melichar, 1914).
Studies carried out since 1960 on Nudaurelia cytherea cytherea (Fabricius). an insect well known for its economic impact on exotic plantations in the Western and Southern Cape, have shown that gynandromorphs of this species are not common. Out of approximately 250 000 moths handled, only five gynandromorphs were obtained. Four of these were bred from caged pupae while the fifth was found live in the field. The latter was kept caged with normal fresh male and female moths but no attempt by these to mate with the abnormal individual was noted. However, this gynandromorph managed to lay some eggs. showing that functionally it acted as a female.
The species descriptionbed by Naude (1926) as Aconura acuminata. Deltocephalus campanus and D. atrodenlatus are only represented by females and they are not redescriptionbed, as no males can as yet definitely be associated with them - likewise also D. africanus, of which no specimens have remained in the collection.
A leafhopper, Dalbulus distans Linnavuori, originally descriptionbed from Argentina, is transferred to a new genus, Afrosteles. It has a wide distribution in South Africa and its alleged Argentine distribution is possibly an error.
The association between ants and various species of homopteran insects is a well-known phenomenon which has been comprehensively reviewed over the past 20 years by Nixon (1951), Way (1963) and by Wilson (1971), So far as the scale insects (Coccoidea) are concerned it may be concluded from these reviews that all the information until about three years ago has been exclusively on the associations of ants with honeydew-producing coccids, e.g. Coccidae, Lacciferidae, Pseudococcidae.
New species Bittacus erythrostigma from Zaï¿½re (Congo) and Uganda and Bittacus tuxeni from Guinea are descriptionbed and illustrated. Ranges of other species arc extended by new distributional records.
This paper is largely based upon the external features of mature larvae, but also provides an account of the ontogenetic changes that occur during larval life. The principal objective is to give comparative data on allodapine larvae, for use in examinations of their classification and of the functions of the peculiar larval projections and hairs which are characteristic of the group.
This paper concerns the external features of mature larvae of two South African genera of allodapine bees, One of them, Allodapula, ranges northward to Rhodesia and possibly beyond (Michener, 1975b) but all the larval material available was collected by me in South Africa, Also included ill a brief account of the ontogenetic development of the one species for which enough larvae of various ages are available.
This paper deals with the taxonomy of 22 Aedimorphus species occurring in southern Africa and in which the tarsi lack distinctive pale markings. These species formed a dominant part of the aedine fauna collected during arbovirus field studies in South Africa and it was the experience that much of the adult female material collected could not be identified beyond the subgeneric level.
Mites of this family are poorly known and this is the first record of them from Africa. The species descriptionbed in this paper were collected from debris under Acacia and Eucalyptus trees but they are also known to occur in hard, dry clayey soil.
Solanum elaeagnifolium Cav. has become a troublesome weed of pasture and cultivated land in South Africa, where attempts at chemical control have been unsuccessful. The life-cycle and host specificity of the Argentine beetle Gratiana lutescens (Boh.), reported to be a voracious defoliator of the weed, were studied under quarantine conditions at Stellenbosch.