44 NAT1CA. 



N. Gallapagosa (fig. 71); N. perspicua (fig. 91); N. Salango- 

 ensix (fig. 70) of Recluz, and Var./wsca, Carpenter (fig. 2), are 

 synonyms. 



N. BIFASCIATA, Gray. PI. 18, fig. 75. 



Light fawn-brown, white next the suture and around the um- 

 bilicus, with two narrow white bands ; umbilicus narrow, chestnut- 

 brown, partly covered above with the brown-tinged columellar 

 callus; interior light flesh- or chocolate-brown, showing the bands. 



Length, 1-25-1*75 inches. 



Acapulco, Gtiaymas, Cape St. Lucas, L. Calif. 



N. SUFFUSA, Reeve. PI. 19, fig. 87. 



Conic ovate, solid, smooth, transparent white, here and there 

 opaque, tinged with violet towards the apex ; columellar callosity 

 violet, nearly covering the umbilicus. Length, 12 mill. 



New Ireland. 



Is probably a variety only of N. mamilla ; but I have not 

 seen the species. 



N. CONICA, Lam. PI. 18, figs. 76, 77. 



Elongated conical-ovate, a little compressed and whitish or 

 orange-tinted at the suture ; balance of shell fulvous ash-color, 

 fading to white at the base ; columellar callus heavy, almost 

 filling the umbilicus which, with the callus, is more or less 

 tinged with chestnut-color. Length, 1-25-1-75 inches. 



So. Australia. 



N. ustulata, Sowb. (fig. 77) appears to be only a slight variety. 



N. PYRAMIS, Reeve. PL 17, fig. 68. 



Solid, conical ovate, whitish or yellowish-white; columellar 

 callus thick, white, partly covering the narrow umbilicus. 



Length, 28 mill. 



Australia. 



I think this will prove to be an uncolored form of the pre- 

 ceding species. 



N. PLUMBEA, Lam. PI. 18, figs. 78, 79 ; PL 19, fig. 88. 



Conically ovate, rather solid, growth striae ruguse at the suture ; 

 leaden gray, lighter or orange-banded at the suture ; umbilicus 



