458 CENSUS OF THE MARINE MOLLUSCA OF TASMANIA, 



LiTTORiNA Eddi^, Petterd, MS. 



Found on seaweed at Kelso, Tamar Heads, but not in a living 

 state, is referable to L. errones, Nevill, and is presumably an 

 accidental introduction. 



FossARUS MiNUTUS, Petterd (Crossed). 



Shell minute, turbinate, solid, smooth, shining, dull white. 

 Whorls four, convex; apex bluntly rounded. Peristome entire; 

 outer lip varicosely much thickened, ecurved; basal lip interrupted 

 in the middle by a wide deep notch; columella rounded (broad 

 but not flattened), thickened medially, to simulate a tooth, 

 opposite to the linear umbilical chink. Length 1"1, breadth 

 0-7 mm. 



The unique example cannot satisfactorily be referred to 

 Crossea, even though its sinuated front lip were accidentally 

 formed, which it does not appear to be. Its reference to Fossarus 

 is doubtful. 



Adeorbis Vincentiana, Angas. 



The very juvenile state of this species offers some marked 

 characters, unsuspected in adult examples already known up to 

 which they have Ijeen traced. 



Shell rather patulous, hemispherically depressed, thin, orna- 

 mented on the penultimate whorl by elevated lamell?e-like ridges 

 becoming closer and finer with the growth of the shell. Pullus, 

 marked at its junction with the spire by a thick varix. consists 

 of two and one-half translucent whorls, the last of which is 

 roundly angulated and 3- to 4-carinated. Base defined by an 

 angulation commencing at the upper margin of the aperture, 

 which curves round the umbilical crater to join the outer edge of 

 the front lip; the umbilical margin curves round to join the end 

 of the straight columella. Aperture somewhat obliquely trape- 

 zoidal; outer lip widely arched; front lip obliquely transverse and 

 straight except at its junction with the columella, where it forms 

 a narrow sulcus. Length and breadth, 2*2 mm. 



