Mr. A. G. Butler on three new Homo^tera. 311 



nature ; and it is on this point that the whole question of herma- 

 phroditism or unisexualitj must be decided. The testes of 

 Asellus aquaticuSj on the external resemblance of which to 

 the supposed testes of his parasitic forms Mr. Bullar relies, have 

 an unusually marked and characteristic histological structure. 

 They contain very large mother cells, in which the long fila- 

 ments of the developing spermatozoa are coiled in bundles. 

 Although Mr. Bullar has examined his Isopods in all stages, 

 and in the fresh as well as prepared conditions, he gives no evi- 

 dence as to any such structure in the supposed testes of these 

 animals : he merely says that the organs " are filled with a 

 cellular blastema, from which doubtless the spermatozoa are 

 developed." 



It seems to me that the absence of positive evidence that the 

 spermatozoa are thus developed constitutes a serious flaw in 

 the chain of evidence by which Mr. Bullar seeks to establish 

 his conclusion. Testis-tissue is not by any means a difiicult 

 object for histological observation ; and since it is evident, from 

 the detailed description which Mr. Bullar gives of the minute 

 structm-e of the ovaries in his Isopods, that he has carefully 

 studied the histology of their generative organs, he could hardly 

 have overlooked definite testis-structure had such existed in 

 the objects which he terms testes. 



I cannot but consider that it will be more prudent to await 

 further evidence before accepting as demonstrated the fact that 

 the members of the subfamily of the Cymothoinge alone amongst 

 Isopods are hermaphrodite — although, were this conclusion 

 confirmed, it would be of great interest, and might be con- 

 sidered as paralleled by such instances as the hermaphroditism 

 of the Serranidae amongst fishes. 



XXTX. — Descriptions of tliree Homopterous Insects in the 

 Collection oftlie British Museum. By Arthur Gardiner 

 Butler, F.L.S. 



Platypleura, Amyot & Serville. 

 Platypleura nicobarica^ n. sp. 



Allied to P. fulvigera from the Philippines, but larger, with 

 the tegmina longer, the whole of the spots crossing the coria- 

 ceous area testaceous, those crossing its apex smaller ; the 

 blackish transverse spots considerably smaller ; wings longer, 

 the subapical transverse fulvous fasciole replaced by three or 



22* 



