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XVI. Notes on South African insects. By J. P. 

 Mansel Weale, B.A. 



[Read April 3rd, 1878.] 



On some insects found on Acacia horrida, and pro- 

 tected hy resemblances to various parts of that tree. 

 Foliage imitators. — The foliage of Acacia horrida is bi- 

 pinnate ; at the base of each leaf on the foot-stalk is a 

 somewhat ovate gland, which yields a gummy secretion. 

 The yonng leaves which appear after rain, irrespective of 

 the season of the year, have their pinnas closely appressed ; 

 they are brilliant golden-green in colour, with a tinge of 

 orange-crimson, and shine very brightly from the exuda- 

 tion of a kind of gummy vai"nish, which becomes hard 

 towards noon in hot weather, and, I believe, protects them 

 from the excessive evaporation they would otherwise 

 suffer. The thorny stipules in this stage are coloured 

 nearly the same as the foliage, but with age, in dry dis- 

 tricts, become white, assuming different shades of colour, 

 and also different sizes. The leaves, when full grown, 

 have a brilliant gloss. Towards night they droop and 

 close their leaves, as also in wet weather during the day. 

 From the broken nature of the foliage, and the open 

 situations in which these trees are generally found, it is 

 evident that under a clear sky and a brilliant sun the 

 effects of chequered direct light with that reflected from 

 the foliage must dazzle the eye. These extremely white 

 lights on the foliage of most South African shrubs are 

 painfully conspicuous to the painter. 



The brilliant silvery ornaments Avhich render so many 

 of our South African insects objects of peculiar beauty, 

 and which would apparently make them extremely con- 

 spicuous, under these circumstances admirably disguise 

 them. 



As instances of foliage imitators among Rhopaloceroua 

 and Heterocerous larvjB, Acridiidcz, Locustidce, Manti- 

 da, Hemiptera and Arachnida, may be mentioned the 

 folloAving species: — Ccenohasis avicena, Feld., a small 

 moth allied to Limacodes, Gynanisa Isis, mentioned in 



TRANS. ENT. SOC. 1878.— PART II, (.JULY.) 



