In the telotrophic ovarioles of D ysdercus fasciatus, mononucleate, binucleate and multinucleate trophocytes are seen in the germarium. Cellular breakdown of the multinucleate cells is seen in the posterior part of this tissue. The nutritive cords, which are continuous with the trophic core at the one end and the oocytes of the vitellarium at the other, contain material of fibrous appearance which continues into the trophic core. The ovariole is enclosed in two sheaths throughout its length. Prefollicular tissue in the germarium appears to give rise to the follicle cells. Mitosis is common in this zone. Oocytes are at first surrounded by a multilayered epithelium. This is later reduced progressively to one layer. This one layered follicular epithelium is at first columnar but then changes to cuboidal mononucleate, cuboidal binucleate and finally to a squamous binucleate condition. This epithelium thus seems to accommodate the increased volume of the oocyte by growth and a change of shape. The oocyte grows fastest at those times when it is surrounded by cuboidal and squamous epithelial cells.

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This study investigated Zambian importation, distribution and use of agricultural pesticides. Data was collected by interviews, questionnaires and direct observation at international, national, warehouse and user levels. A wide range of pesticides is available. Imports and distribution are controlled by a few multinational companies (MNC's). No government control exists on types or amounts imported, and on distribution, packaging or labelling. Safety information is virtually non-existent. Some Zambianused pesticides are under restriction in the West. The total amount used seems to be increasing. Harmful health effects have been observed. The number of involved MNC's appears to be increasing.The largest amount of imported pesticides is used by government in large scale medical and agricultural control schemes. In agriculture, large-scale farmers use most pesticides, but small-scale farmers are now beginning to use greater amounts and more types.Most MNC's see this latter sector as a large future market. Most fanners get pesticide information only from MNC's. By comparison, the Extension Service is inadequate. Consequently, the authors suggest that the following are needed: A broad based Zambian advisory committee on pesticides; government legislation of importation, distribution, packaging, labelling and safety; and Extension Service expansion.