SuTER. — On New Zealand MoUusca. 121 



Art. VIII. — Further Contributions to the Knoioledge of the 

 Molluscan Fauna of Neto Zealand, with Descriptions of 

 Eight neio Si^ecies. 



By Henry Suter. 



Communicated by Professor Huttou, 



\B,ead before the Philosophical Institute of Canterbury, 1st November, 



1893.] 



PJates XIV.-XXI. 



1. Large Form of Potamopyrgus cumingiana, Fischer. 



Very large specimens of this shell were kindly presented to 

 me by Professor P. W. Hutton. They were collected in Lake 

 Te Anau, and are 8mm. high by 4mm. diameter. The 

 whorls, of which there are eight, are very strongly and 

 broadly angled round the upper part, and the last three show 

 traces of the rubbed-off spines, of which there were about 

 sixteen on the body-whorl. 



This species is very limited in its distribution on the South 

 Island. I have much smaller specimens from Pelorus Kiver 

 and Collingwood only. 



2. Latia and its Varieties. 



Four species of this genus peculiar to New Zealand 

 have been described — viz., L. neritoides, Gray (1849) ; L. 

 lateralis, Gould (1852) ; L. petitiana, Fischer (1856) ; and 

 L. gassiesiana, Fischer (1856). Mr. Charles Hedley kindly 

 presented me with etchings of these shells, and I am there- 

 fore now in a better position to judge whether they are all 

 good species or only varieties of L. neritoides, Gray, the first 

 described of the lot. Gould himself says that his L. lateralis 

 might probably be the same as L. neritoides, and Professor 

 Hutton (Proc. Linn. Soc. N.S.W., vol. vii., 1883) holds that 

 these two form only one species. To judge, however, from the 

 figures, I am of opinion that L. lateralis and L. gassiesiana 

 must be considered as varieties of L. neritoides, and very 

 likely also L. petitiana, though the figure does not show a 

 very marked difference from L. neritoides. 



3. Ancylus dohmianus, Clessin (1882). 



The description and figures of this shell, which is said to 

 come from New Zealand, were published in Conch. Cab. (2), 

 Bd. I., Abth. vi., p. 54; pi. viii., fig. 8 (two). It resembles 

 somewhat A. irvince, Petterd, from Tasmania, but the apex is 

 quite different. Neither Professor Hutton nor myself have 

 any knowledge of such an Ancylus ever having been found in 



