258 MAZATLAJif UNIVALVES 



Genus IS'EEITI^'A, Lam. 

 Neritella, Kv/raph—H. ^' A. Ad. Gen. vol i. p. 380. 



323. JSTeeitina cassicttlttm, Sow. 



Couch. Bl. f, bo.—TIies. Conch, p. 521, no. 47, pi. 115, f. 194.— 



Mke. in Zeit.f. Mai. 1850, p. 116, no. 19.—^. Sf A. Ad. Gen. 



i. 382. 

 Comp. N. faba, Sow. Thes. Conch, p. 530, no. 78, pi. 115, f. 219— 



221.— Co;^c/^ III. f. 10.— ( = Clitlion f. S. ^ A. Ad. Gen.i. 



385.) 

 Comp. xTeritina Californiea, Rve. Conch. Ic. pi. 4, sp. 20, f. 20, 



a, b. (Gulf of California, Miis. Cuming.) 



Altliougb. picked specimens may be found so far distinct 

 from JST. picta that Messrs, Adams have placed them in differ- 

 ent subgonora, individuals may be found in each species so 

 nearly alike that it is not impossible that they may ultimately 

 prove to be identical.* They display exactly the same varieties 

 of form, although they are much more constant in colour. The 

 differences observed are as follo'vs. This species is larger ; 

 mouth -white and stained with orange ; inner lip rather flat- 

 tened; teeth smaller and more irregular, more resenjbling 

 those of N. virginea ; operculum longer, with broader dark 

 border, richer orange colour within, and medial line scarcely 

 marked. If J^T. faba does not differ more than is stated in 

 Sow.'a description, it may prove identical. He characterizes it 

 as resembling N. picta, but having "the spire rather more 

 hidden, and the columella neither swelled [? swollen] nop of a 

 chesnut colour." It belongs however to another genus, teste 

 S. ^ jl. Aa Whether these and connected species in the 

 Pacific oe reahy distinct from N. virginea with its many-named 

 varieties from the Atlantic, it must be for those to judge who 

 have examined large scries from different localities. The form 

 exists in the B. !M. from China, Philippiue Is., and Port Essing- 

 ton. It is found on the coasts of Spain and reaches Dalmatia. 

 A regularly formed sp. measures long. '68, lat. "83, diiK 120". 



A flattened „ „ '57, „ -72, „ 145". 



An elevated „ „ '73, „ '77, „ 90". 



• As 8uch I have freely distributed specimens. It is not nnlikely that Prof. 

 Adams regarded them aa the same. "The specimens which Lieut. Green col- 

 lected are of extraordinary size." Fan. ShMs, p. 207. 



