292 BULLETIN OF THE 



Family NATICID^. 

 Genus NATICA Lamarck. 

 Section COCHLIS Morch. 

 Operculum shelly, with a single marginal rib. 



Natica maroccana (Chemnitz) Dillwyn. 



Nerita maroccana Chemn., Conch. Cab., V. p. 270, pi. clxxxviii. figs. 1905-1910 ex 

 parte. Ulysses' Travels, p. 474. Dillwyn, Cat. Hec. Shells, 11. p. 983, No. 13, 

 1817. (West Indies, W. Africa, Mediterranean.) 



Natica Dilhcynii Payr., Moll. Corse, p. 120, pi. v. figs. 27, 28, 1826. 



Natica proxima C B. Adams, Contr. Conch., p. HI, 1850. Eeere, Conch. Icon. 

 Aaf/ca, fig. 126. (West Indies.) 



Habitat. Mediterranean, West Africa, West Indies, and northward to Cape 

 Hatteras, N. C. 



This species, as eliminated from the mixture of species called maroccana and 

 marochiensis by Dillwyn, should stand as the genuine maroccana. That the 

 N. proxima Adams is identical with authentic N, Dillwynii Payr., I have deter- 

 mined by the comparison of types. The West American maroccana is a dififer- 

 ent species, and has a different operculum. N. proxima has an entirely different 

 operculum from N. canrena, with which Tryon unites it (as the young), and 

 belongs to a different section of the genus, as already pointed out by Morch. 

 On the other hand, N. Dillwynii and avellana Philippi, which are identical 

 with N. proxima, are regarded by Tryon as distinct. He refuses the name 

 maroccana or marochiensis to the Mediterranean form, which is really identical 

 with that of the West Indies, and unites with the latter the West American 

 species, which is perfectly distinct. This group, in fact, is in great need of 

 thorough study by some one who will treat the subject with care, and work 

 from the specimens, and not jump to conclusions from the inspection of more 

 or less inaccurate figures. This group and that of N. canrena are particularly 

 muddled, and inconsiderate wholesale lumping of species can in the present 

 state of our knowledge do nothing but harm. I have not pretended to give 

 even a small proportion of the synonymy. The operculum of this species has 

 a double marginal rib, the outer half higher than the inner, and the whole, in 

 adult specimens, separated from the central area by a rather broad flat-bottomed 

 channel. The nucleus of the operculum is usually overlaid by a thin irregular 

 callus, often of a dark color. 



"} 



Natica livida Pfeiffer. 



Natica livida Pfr., Wiegm. Arch., VI. p. 254, 1840. Morch, Malak. Blatt., XXIV. 



p. 64, 1877. 

 Natica jamaicensis C. B. Adams, Contr. Conch., p. Ill, 1850. 



