164 Transactions. — Zoology. 



Patula ida, Gray (ide). PI. ix., fig. u. 



Animal with the body rather short and narrow ; mantle sub-central, 

 rather anterior, slightly reflected over the peristome of the shell ; foot 

 narrow, extending behind the shell, the tail truncated and furnished with a 

 mucous gland : no locomotive disc. Eye-peduncles very long, cylindrical, 

 approximated at their bases ; tentacles long. Colour pale olive-brown 

 spotted with dark brown ; a longitudinal dark brown line runs round the 

 side of the foot, below which it is edged with alternate, transverse, bars of 

 brown and pale olive-brown. 



Jaw, with about 30 flat ribs, each transversely striated. 



Dentition, 22-1-22. Laterals about 8. 



Central tooth rectangular, longer than broad ; the reflexed portion tri- 

 cuspid, extending over a third of the base, the median cusp long and 

 straight, but not reaching the posterior margin, the cutting point rather 

 large, projecting beyond the margin ; the side-cusps constricted on the 

 outer side. Laterals like the central, but rather oblique, the outer side- 

 cusps being larger than the inner. Inner marginals with a single bidentate 

 cutting point ; outer marginals broader than long, with several cutting points. 



Hab. Greymouth (E. Helms). 



Patula cornictjlum, Eeeve (= eta, Pf.). PL ix., fig. f. 



Animal like coma, but the eye-peduncles smaller and not clavate. 

 White, slightly speckled with grey above ; peduncles purplish. 



Jaw finely striated. 



Dentition, 14-1-14. Laterals 4 or 5. 



Central tooth rectangular, longer than broad ; the reflexed portion about 

 half the length of the base, tricuspid, the middle cusp long, extending to 

 the posterior margin and armed with a small point. Laterals like the 

 central tooth, but the middle cusp more clavate. Inner marginals with 

 one, and outer with three acute points. 



Hab. Eyreton, North Canterbury (C. Chilton). 



In the shell the interstices between the ribs are finely reticulated. 



Patula infecta, Eeeve (= zeta, Pf.). PI. ix., fig. h. 



Animal like coma. White, eye-peduncles and a stripe on each side of 

 the head greyish. 



Jaw finely striated. 



Dentition, 15-1-15. Laterals 3. 



Central tooth rectangular, broader than long ; the reflexed portion 

 tricuspid ; the side-cusps constricted on the outer side ; middle cusp reach- 

 ing to the posterior margin and the cutting point projecting beyond. First 

 lateral like the central ; the others smaller, bicuspid, the inner cusp small, 

 the outer long, narrow, and with a small point. Marginals tridentate, the 

 denticles nearly equal in size. 



