MAZATLAN UNIVALVES 453 



or less closed. The largest (which is very thin) is probably 

 N. ovum, Mice. 2058, 6 sp. normal form, open umbilicus. 

 2059, 4 do. umbilicus more or less closed. 2060, 4 sp. acumin- 

 ated form, umbilicus open. 2061, 5 do, umbilicus more or less 

 closed. One sp. has a second umbilical groove. 



FAMILY LAMELLARIADJE. 

 GENUS LAMELLARIA, Mont. 



Lamellaria, Mont. Linn. Trans. 1825, vol. xi. p. 184 (pars). 



H. $ A. Ad. Gen. vol. i. p. 201. 

 Marsenia, Leach. Phil. Handb. Conch, p. 163. 



577. LAMELLAEIA , sp. ind. (a.) 



Tablet 2062 contains a minute white shell, measuring '065 by 

 '047, having one whirl and a half, with coarse strise of growth, 

 and reflected labium. 

 Hob Mazatlan ; 1 sp. off Chama ; L'pool Col. 



578. ? LAMELLAEIA , sp. ind. (b.) 



Tablet 2063 contains a fragment which may belong to Lamel- 

 laria or even to an Atlantid. It possesses a stout globular nucleus 

 of two rounded whirls, white and glossy, large (as compared 

 with Vitrinella) and rapidly increasing ; with a portion of a 

 flat expanding outer whirl, the texture of which may have 

 been, when fresh, somewhat gelatinous, and in its dried state 

 is transparent and very finely wrinkled. 

 Hdb. Mazatlan ; 1 broken specimen off Spondylus ; L'pool Col. 



FAMILY FICULIME. 

 GENUS FICULA, Swains. 



Sycotypus, (Browne,) H. Sf A. Ad. Gen. vol. i. p. 198. 

 Pyrula, pars, Lam. 



[579. FlCULA VENTEICOSA, Sow. 



Pyrula ventricosa, Sow. Tank. Cat. no. 1614, App. p. 16, 1825. 

 Kien. Icon. Conch, p. 27, pi. 12, f. 2. Lam. An. s. Vert. 



