660 DESCRIPTIONS OF TWO NEW SPECIES OF AUSTRALIAN MOLLUSCA. 



intermediate portion of the side being quite free from sulcation. 

 The margin of the right side of the shell is blunt, well-defined, 

 and everted, separating the dorsal and ventral surfaces, and runs 

 forwards and backwards, joining the everted extremities. The 

 teeth of the orifice, from 16 to 18 in number, are white, sharp, 

 and prominent, but not coarse on the right side, and only extend 

 about half-way across the right callous base ; on the left the 

 teeth, about 15 in number, are small and fine, scarcely extending 

 at all across the left side of the base, but are seen as callosities 

 dipping into the internal stoma. 



The channel is well everted. There are no decided colour- 

 markings on each side of it in front, merely a light brown 

 •coloration blotch, and a similar faint coloration blotch is 

 noticeable on the sides of the posterior ends. There is a faint 

 freckling of coloration along the everted edges of the sides 

 within the sulcation of the margin ; the rim margin is inclined to 

 be tuberculously elevated. The interior of the shell is of a very 

 pale flesh tint. 



Length 25, breadth 14 millimetres. 



B^ab. — North-west coast of Australia. 



Cyprcea stolida, Linn., with its variety C. hrevidentata^ Sowb., 

 and C. Coffea^ with which this species would group, are found at 

 the same locality, but it has such distinct difierences as to justify 

 its being made a new species. 



I have named this shell after Mrs. J. F. Irvine, an enthusiastic 

 conchological collector, who obtained it at Cape Naturaliste, in 

 Western Australia, along with many other valuable species new 

 to science 



EXPLANATION OF PLATE. 



Figs. 1-3. — Ancylus Smithi, Cox ( x 6). 

 Fig. 4. — C(xliaxis australis, Forbes ; the animal. 



Fig. 5. — Cceliaxis australis, Forbes"; animal and shell (enlarged). 



Fig. 6. — Cceliaxis australis, Forbes ; section. 



Figs. 7-9. — Gyproia Irvineance, Cox. 

 Figs. 10-11. — Helix Rowe-insulce, Cox. 

 Xote. — Figures 4-6, and 10-11 refer to species to be treated of in a fiiture 

 paper. 



