The Bionomics of South African Insects. 871 



on the ground and rocks, arc very liable to be attacked, 

 but in South Africa at least, species which haunt bushes 

 and trees and fly high arc not likely to fall a prey to 

 lizards, and birds arc the only probable enemies when no 

 traces have been left by a mantis. In the description of 

 Plates IX, X, and XI, a brief account of the habits of each 

 South African species is given by Mr. Marshall together 

 with the conclusion which appears to be justified. 



A very interesting general conclusion emerges after this 

 consideration and comparison of all the specimens here 

 figured, viz. the bionomic meaning of important elements 

 in pattern, and important structural developments of the 

 wings of Lepidoptera. On Plate IX we sec evidence that 

 injury at the apical angle of one or both fore-wings is 

 fairly common. Now this angle is very remote from the 

 vital parts, and no great harm to the butterfly is done by 

 such injury. And this is a part of the wing which is 

 constantly rendered specially conspicuous below as well as 

 above by apical and sub-apical white spots and bars, black 

 tips, patches of bright colour, and by eye-spots (Plate IX, 

 figs. 1, 3, 15, IG, 20, 21, 22, 23, 25 ; Plate X, figs. 3, 8, 19, 

 25, 28, 32, 33 ; Plate XI, figs. 4, 21, 22, 23, 24). In the 

 four lowest figures on Plate XI the conspicuous apical 

 marking has been injured and, in three cases out of four, 

 partially or entirely shorn off on one side. This interpre- 

 tation of the meaning of the apical colour-patches was 

 suggested by Mr. Marshall in sending these very speci- 

 mens, and he alluded to two out of tiie three butterflies 

 figured on Plate XI, figs. 21-23, in the following passage: — 

 '^Salisbury, June 20, 1899. — I would suggest that these 

 bright patches of colour [in the orange- and purple-tipped 

 Tcracoli\ which were doubtless first developed by sexual 

 selection, have been of further use in diverting attack 

 from the vital parts, and this may perhaps explain their 

 almost universal transmission to the female sex. I have 

 sent you two good examples supporting this view, in that 

 the orange tip of one wing has been snipped off, presumably 

 by a bird. It should however be noted that the innyle 

 tips are very inconspicuous in flight, and perhaps this might 

 account for the markedly-swifter flight of those species 

 which possess them, as they will have thus lost a useful 

 protection through the action of sexual selection, and have 

 compensated it by increased swiftness." * 

 * Dr. F. A. Dixey points out to me that it is iu favour of tlii.s 



