230 NEWTONIELLA. 



which has, typically, merely a rudimentary notch on the anterior 

 margin of the aperture. 



Type. — Cerithiiim metula, Loven. 



Newtoniella cribarioides, Tenison- Woods (sp.). 



1879. Cerithium cribarioides, Tenison-"Woods, Proc. Linn. Soc. N.S.W. 



vol. iii. p. 231, pi. XX. fig. 14. 

 1893. Cerithium cribarioides, Tate and Dennant, Trans. Eoy. Soc. South 



Aust. vol. xvii. pt. 1, p. 222. 



Shell elegant, turreted, slender ; whorls to the number of four- 

 teen, typically convex, but frequently slightly angulate anteriorly, 

 having bold spiral threads crossed by longitudinal threads, pro- 

 ducing retiform ornament ; spiral threads three or four in number, 

 the most anterior being at the margin of the angulation when that is 

 present ; sutures much cut in ; anterior of the body-whorl flattened, 

 smooth, interrupted by growth-lines, keeled at the periphery, and 

 having a single spiral thread inside ; aperture subquadrate ; 

 outer margin thin ; columella twisted ; anterior canal long and 

 slightly twisted. 



The protoconch is not preserved in any of the examples in the 

 Museum collection. N. cribarioides may be compared with the 

 European Eocene N. acceiens, Deshayes. It is an extremely 

 variable species. 



Dimensions. — Length 33'5mm.; breadth 8 mm. 



Form, and Loc. — Eocene : Victoria. 



48052. Several examples in which the anterior angulation of 

 the whorls is well developed ; from Hobson's Bay. Purchased. 



73226. Example of the adult ; in the earlier stages of the 

 growth of this shell the longitudinal threads are very close 

 together, and persist with regularity until the ephebic stage, where 

 they are much opened out. During that stage these threads 

 gradually become still closer together, and smaller in size, 

 producing granulation by crossing the spiral threads. From 

 Brighton. Purchased. 



G. 4155. Specimen of the neanic stage of growth ; from 

 Muddy Creek. Presented by John Dennant, Esq. 



