268 MAZATLAN UNI VALVES 



GENUS NEBITINA, Lam. 

 Jtf-eritella, Humph. H. fy A. Ad. Gen. vol i. p. 380. 



J^ 328. NEEITINA CASSICULUM, Sow. 



Condi. III. f. 55. TJies. Conch, p. 521, no. 47, pi. 115, , 194 



Mke. in Zeit.f. Mai. 1850, p. 116, no. 19. If. & A. Ad. Gen. 



i. 382. 

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



221. Conch. IU. f. 10. ( = Clithon f. H. & A. Ad. Gen. I 



385.) 

 Comp. Neritina California, Eve. Conch. Ic. pi. 4 sp. 20, f. 20, 



a, b. (Gulf of California, Mus. Cuining.) 



Although picked specimens may be found so far distinct 

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

 ent subgenera, 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 follows. This species is larger ; 

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

 tened; teeth smaller and more irregular, more resembling 

 those of JN". virginea ; opereulurn longer, with broader dark 

 border, richer orange colour within, and medial line scarcely 

 marked. If N. faba does not differ more than is stated in 

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

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

 hidden, and the columella neither swelled [? swollen] no* of a 

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

 H. 6f ^L. Aa Whether these and connected species in the 

 Pacific oe realiy distinct from JS". virginea with its many-named 

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

 have examined large series from different localities. The form 

 exists in the B. M. from China, Philippine 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, div. 120. 



A flattened '57, '72, 145. 



An elevated '73, *77, 90. 



* As such I have freely distributed specimens. It is not unlikely that Prof. 

 Adams regarded them as the same, "liie specimens which Lieut. Green col- 

 lected aro of extraordinary size." Pan. Shells, p. 207. 



