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XIV. Notes on Seasonal Dimorphism in South African 

 Rhopalocera. By Guy A, K. Makshall, F.E.S. 



[Read May Gth, 189G.] 



I AM mucli pleased to observe that the very important 

 and long-neglected subject of Seasonal Dimorphism in 

 African Butterflies is at last receiving the attention of 

 so eminent an authority on entomological matters as 

 Mr. A. G. Butler, and I trnst that the short paper before 

 me will soon be supplemented by many of a like nature, 

 for it is liigh time that the nomenclature of African 

 lihopalocera, and more especially the Plerila', should be 

 thoroughly revised from the standpoint of seasonal varia- 

 tion. The opinions expressed by my friend, Mr. Cecil 

 W. Barker, in his most interesting paper on this subject 

 (Trans. Ent. Soc. 1895, p. 413) will, I think, be upheld 

 by all South African lepidopterists who have taken the 

 trouble to investigate the matter, though I consider his 

 rule that the dry season form is generally smaller than 

 the wet season one to be inadvisable, for the exceptions 

 to it certainly equal if they do not exceed the illustrations 

 of it. Mr. Butler's remai-ks on the group of Teraoli, 

 represented by T. vesta, Reiche, are in every way excellent, 

 but when he proceeds to discuss the seasonal forms of 

 the genus Acrsea we have an instructive example of the 

 extreme difficulty in accurately defining the specific 

 differences of butterflies merely from a series of museum 

 specimens when not backed up by a practical knowledge 

 of the habits and range of the species involved. Indeed, 

 I have not the slightest hesitation in stating that, in the 

 present instance, the results arrived at are entirely in- 

 correct and misleading. Here is Mr. Butler's provisional 

 revision of the Acrita group : — 



Dry season form. Wet season form. 



(1.) Acnva uiulcvcoh, Trim. ^ Acrcca bomba, H. G. Smith. 

 (2.) Aa-ica guillemei, Oherth. = Acraa periphanes, Oberth. 

 (3.) Acnea doubledai/i, Guer. = Acrcca dircaea^ Westw. 

 (4.) Acraa stenobea, Wallg. = Acnea caldarena, Hew. 

 (5.) Acrcea pudorina, Staud. = Acraa chceribida, Oberth. 



TRANS. ENT. SOC. LOND. 1896. — PART IV. (dEC.) 



