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are described. The complete life-history averages 49 days. The eggs- 

 are deposited in clusters on the iinder-surface of leaves and under 

 field conditions were first observed during the last week of October. 

 The larvae feed upon the lower epidermis of the leaves only, whereas- 

 the adults almost invariably feed upon the upper. In the insectary 

 the larvae nearly always pupated on the soil, but under natural 

 conditions they do so in sheltered spots on their food-plants. In 

 Pretoria and in the neighbourhood of Johannesburg two generations 

 were observed during the season. The eggs of the first were deposited 

 on 30th October 1914 and the adults emerged on 26th December. 

 Those of the second generation were deposited on 11th January 1915- 

 and the adults emerged on 28th February. E. dregei is distributed all 

 over the Union of South Africa and also occurs in Ehodesia. The 

 food-plants include the potato, pumpkin, vegetable marrow, cucumber, 

 turnip, radish, melon, bean, spinach and wild Solanaceae. The injury 

 is caused by the larvae and adults consuming the leaf-tissue, the chief 

 damage being undoubtedly caused by the former. On one farm nearly 

 15 acres of potatoes were destroyed. The beetles hibernate during 

 the winter and early spring under the bark of eucalyptus trees, stones, 

 and rubbish near gardens and potato fields. It was found easy to^ 

 control both larvae and adults owing to their sluggish habits and their 

 tendency to remain on particular leaves until these have been entirely 

 skeletonised. It is essential that spraying should be begun directly 

 the larvae are observed on potato foliage, as they are markedly 

 gregarious for the first two weeks. A spray containing 3 lb. of lead 

 arsenate paste to 50 gals, water is efficient, but care must be taken 

 to spray both the upper and lower surfaces of the leaves. For 

 large areas, where economy is a consideration, an excellent substitute' 

 consists of 1 lb, Paris green to 100 gals, water, to which 2 lb, unslaked 

 lime is added, 



GuNN (D.). The Plum Slug Caterpillar, Parasa latistriga. — Union 

 S. Africa. Dept. Agric, Pretoria, Div. Entom. Bull. no. 7, 1916, 

 7 pp., 4 figs. [Received 19th July 1916.] 

 The dark brown, oval cocoons of the Limacodid, Parasa latistriga- 

 (plum slug caterpillar) are common on the leafless deciduous fruit and 

 oak trees of Pretoria, being found on apple, peach, plum, nectarine,, 

 apricot, oak and sycamore. The chief injury is done to plum and oak 

 trees. This species may have an even wider range of food-plants, espe- 

 cially as it occurs in other parts of South Africa. The various stages- 

 are described. The life-cycle of the first generation of P. latistriga 

 averages 93 days, the second occupying about nine months. The 

 larva is compared in detail with that of P. Johannes, which closely 

 resembles it and is also a pest of oak trees. During November and 

 December several parasites emerged from cocoons in the insectary,, 

 but as only 3 per cent, were parasitised, this natural control is not 

 important. A spray containing 3 lb. of lead arsenate paste to 50 gals, 

 of water readily destroys the larvae, provided care is taken to spray the 

 under side of the leaves thoroughly, and should be employed before the 

 larvae have abandoned their gregarious habits. Paris green in the 

 proportion of 1 lb. to 80 gals, of water, to which 1 lb. of unslaked lime 

 is added, is an excellent substitute for arsenate of lead paste where- 

 economy is necessary. 



