124 Lt.-Colonel H. H. Godwin-Austen on 



and in its place some uniform tint pervaded the whole 

 visceral sac up to its position in the apical portion of the 

 shell. 



1 was first led to notice specific variation in this part of 

 the animal lying within the shell when going over a large 

 collection of species of Macrochlamys from Sikliim. I have 

 laid stress on the character very fully in the descriptions of 

 species in this paper, trusting that it may be useful in their 

 determination, particularly of local varieties. 



It is apparent and worthy of notice that these South- 

 African snails, hitherto placed in the genus Helicarion, have 

 characters, external as well as internal, not at all like those 

 of typical species of the genus, viz. //. cuvi'eri and hyalina 

 of Australia, previously alluded to. 



They differ also from species inhabiting India and the 

 Malay Archipelago, Malayana, &c., at one time also placed 

 in llelkarion, I have good grounds, therefore, for locating 

 the South-African species in a new subfamily, for which I 

 propose the name Peltatinse, particularly as the species 1 have 

 now examined from South Africa can be readily separated 

 into several well-defined genera. 



Unfortunately I have not that personal knowledge of the 

 physical features and the local distribution of the fauna and 

 fiora of South Africa which is so desirable when writing a 

 ])aper such as this. All I have seen of the country is the 

 immediate neighbourhood of Cape Town and Simon's Ba}', 

 for the vast extent beyond that I am indebted to books of 

 travel and meeting those who have been there. 



Like Southern India it is a land of great antiquity, a 

 very large portion not having been beneath the ocean 

 since pre-Cretaceous times, during which vast changes in 

 sea and land were going on in other parts of the world. 

 There was a period indefinitely associated with the out- 

 burst of volcanic activity in Southern India when the two 

 countries had a land-contiection. This renders a study of 

 the moUuscan fauna of Africa of such extreme interest. 

 Wm. Blanford, writing so long ago as October 1876, in the 

 pages o£ this journal (vol. xviii. p. 277), on "The African 

 Element in the Fauna of India," says : " I was especially 

 desirous also of working out the very difficult question of 

 terrestrial MoUusca, the distribution of which, as^Ir. Wallace 

 has just pointed out in his * Geographical Distribution of 

 Animals,' whilst agreeing in some respects with that of the 

 Vertebrata, presents some very singular anomalies." In this 

 family of the Zonitidiy, although we do not find a single 

 crenus common to Africa and Southern India, yet there is 



