MAZATLAN UNIVALVES 487 



Genus NITIDELLA, Swains. 



Nitidella, Swai7is. (shell.)— Nitidella, Gi-ar/, (operc.) 

 Buccinum, pars, Lam. 

 Columbella, pars, atict. 



Testa ut in Mitrella fHisso, non Swains. IT. ^ A. Ad. Gen. 

 vol. i. p. 183 ;) interdum decollata ; lahio continuo, hand crenato. 

 Operculum elongatum, nucleo laterali, ut in Purpura for matum. 



The operculum of the following species being distinctly 

 Purpuroid, it is necessary to remove it from both Buccinum 

 and Columbella ; and as none of the genera in Purpuridse 

 seemed constituted so as to receive it, the above name (given 

 by Swainson from the shell alone) was adopted by Dr. Gray 

 for such of the Columbella; as might prove to have Purpuroid 

 opercula. It did not seem expedient to adopt the group 

 of Messrs. Adams, till the opercula of other species had been 

 examined ; nor to draw out a more precise diagnosis, tdl it 

 was known how far the peculiarities of B. cribrarium were of 

 specific orof generic value. 



613. NiTIDELLA CEIBEAEIA. 



Buccinum cribrarium, Lam. An. s. Vert. vol. x. p. 176, 

 no. 43. — Q,w<j]/ S^' Gaim. Voy. de I'Astr. Zool. vol. ii. p. 421, 

 pi. 30, f. 21, 2i.—Kien. Leon Conch, p. 45, no. 44, pi. 16, f. 57. 



Columbella cribraria. Sow. Thes. Conch, p. 129, no. 51. pi. 37, 

 f. 112, 113. — Dssh. in Lam. loc. cit. — Gray in Zool. Beech. 

 Voy. p. 129.— -B. M. Cat. Cwh. Moll. p. 27, no. ^Vo.—Mke. 

 (Conch. St. Vine.) in Zeit.f. Mai. 1853, p. 75. 



(Columbella) Mitrella cribraria, S. ^ A. Ad. Gen. i. 183. 



= Voluta ocelata, Gmel. p. 3455. 



=Le Barnet, Adans. Seneg. p. 146, pi. 10, f. 1. 



= Buccinum parvulum, L>kr. in Zeit.f. Mai. 1847, p. 64. — 

 Phil. Ahbild. iii. pi. 2, f. 7. 



=« C. mitriformis, Brod. Sf King, Zool. Journ. — Lister, Conch. 

 pi. 920, f. M, (teste Gray.) 



= C. guttata, Soto. Proc. Zool. Soc. 1832, p. US,,—Mull. Syn. 

 Nov. Test. Viv. p. 88.— C. B. Ad. Pan. Shells, p. 89, no. 89.— 

 (Non Sow. Proc. Zool. Soc. 1841, p. 50 : — Thes. Conch. 

 p. 181, no. 59, pi. 39, f. 121 -. = 0. punctata, do. index, p. 146.) 

 This well marked form appears to be very widely diffused. 



The Pacific ty^e is of course regarded by Prof. Adams as 



distinct from the Caribbasan, as it was at first by Sowerby. It 



