NATICA. 33 



and others the name of N. didyma, Bolten (fig. 81), an author 

 scarcely quotable ; N. vesicalis, Phil. (fig. 92), has also been 

 used in this connection; but N. ampla has priority of position, 

 although published at the same time as N. vesicalis. Other 

 synonyms are: N. robusta, Dkr., N. Lamarckiana (fig. 86), N. 

 Chemnitzii (fig. 82), JV. Petiveriana (fig. 91), and N. intermedia 

 of Recluz ; N. problematica, Reeve (fig. 93) ; N. papyracea, 

 Busch (fig. 85) ; N. bicolor, Schrenck, not Phil. ; N. incisa, Dkr., 

 and perhaps N. glaucina, Lam., not Linn. 



X. BICOLOR, Phil. PL 11, fig. 94. 



Depressed orbicular, smooth, yellowish brown above, whitish 

 beneath ; umbilicus spirally striate, and few ridged, callus small, 

 bipartite, chocolate-color ; aperture dark chocolate above, whitish 

 inferiorly. Length, 28 mill. 



Chinese Sea, Japan. 



Perhaps only a variety of the preceding species. 



X. INCBI, Phil. PI. 10, figs. 81-90 ; PL 11, fig. 95. 



Yellowish-, brownish-, or livid-white, chocolate, etc. ; depressed 

 orbicular ; umbilicus entirely filled with a button-like callus, the 

 rounded margin of which is sometimes deeply grooved ; aperture 

 white, or tinged with chocolate. Length, 1-1 '25 inches. 



Southern Coast of Australia. 



The synonyms are N. Baconi (fig. 95), and N. fibula (fig. 89) 

 of Reeve, and N. clavata, Sowb. (fig. 90). 



X. JOSEPHINE, Risso. PL 10, fig. 84; PL il, fig. 96. 



Depressed globose, widely umbilicated, but the umbilicus 

 mostly filled by the flattened callus ; glaucous or yellowish brown 

 above, usually lighter or whitish beneath, aperture chocolate- 

 colored, white inferiorly. Length, 1 inch. 



Southern Europe. 



It is N. glaucina of Reeve and other authors (fig. 96), not of 

 Linnaeus or Lamarck ; N. olla, Desh. ; N. Pliilippiana, Recluz 

 (fig. 84) ; N. albumen, Scacchi, etc. 



X. DUPLICATA, Say. PL 12, figs. 3-5 ; PL 13, fig. 10. 



More or less conically globose, obsoletely spirally engraved, 

 and obliquely longitudinally striated, often with a slightly 



