BLANFORD : NOTE ON BENSONM M \TXWAl;TXOT. 181 



In March, 1883, Col. Godwin-Austen published in the Journal of 

 the Asiatic Society of Bengal some figures of shells and animals copied 

 from drawings which had been prepared for Dr. Stoliczka, who died 

 in 1874. Amongst these was one, which had been identified by 

 Mr. Nevill with a species named by him Benson/a Mainwarinqi, a name 

 which had not been published until it appeared with the figure of the 

 shell and animal. This figure appears good, and should suffice for 

 the identification of the species, provided a living specimen were 

 available for comparison, so that the specific name Mainwaringi cannot 

 be discarded. Since Mr. Nevill applied the name in manuscript to 

 a shell, of which there were numerous specimens in the Calcutta 

 Museum, and since under the number assigned to the species (272) 

 in the "Hand List of Molluscain the Indian Museum " (p. 49) mention 

 is made of the drawing of Dr. Stoliczka's subsequently published by 

 Col. Godwin-Austen, it is reasonable to infer that the specimen from 

 which the drawing was taken was amongst those recorded by Nevill, 

 because the whole of Stoliczka's collection was in the Indian Museum 

 in Calcutta. The drawing mentioned by Nevill is identified in 

 God win- Austen's paper. A typical adult example of the shell was 

 sent by Mr. Nevill to Col. Godwin-Austen, to whom I am indebted 

 for permission to have the accompanying figure made from it. 



In October, 1883, there appeared Col. Godwin- Austen's description 

 of the shell and animal of Macrochlamys Dalingensis, which was 

 published in part iv of the " Land and Fresh-water Mollusca of India," 

 vol. i, p. 121, pi. xxxv. In the notes on the species the facts above 

 detailed with regard to Nevill's title Mainwaringi are mentioned, but 

 the identification of the figured form is regarded as doubtful, and 

 since the typical specimen of M. Mainwaringi, though evidently closely 

 allied to M. Dalingensis, differs in colour and form, the latter species 

 is described as distinct. The differences are that M. Dalingensis is 

 decidedly darker in colour, that the sculpture above, consisting of fine, 

 close, almost subcostulate striae, decussated by minute spiral impressed 

 lines, is more definite in M. Dalingensis than in M. Mainwaringi, and 

 that in the former, although the lip is thickened and white inside, 

 there is no trace of the white bands across the last whorls, corre- 

 sponding to the formation of successive labiate apertures, during 

 growth, which are so characteristic of the latter. This last difference 

 is, I think, shown to be unimportant by the fact that I possess 

 specimens collected by myself at Damsang, the original locality of 

 M. Dalingensis, with the shell growing beyond the thickened lip, as 

 in M. Mainwaringi. The other differences I should not myself regard 

 as specific, although the shells are doubtless marked varieties, but 

 there is possibly a distinction in the animal, to which Col. Godwin- 

 Austen has called mv attention. In the figure of Bensonia Mainwaringi 

 no shelLlobes are shown. The left shell-lobe woidd be invisible in 

 the position in which the animal is drawn, and I think the right shell- 

 lobe, if short, might also be concealed. It is said to be short in 

 M. Dalingensis, and it is well known that these lobes in Macrochlamys 

 and its allies vary in development at different seasons, being, I think, 

 much larger when the atmosphere is warm and the humidity high ; 



