NATICA. 47 



Related by its coloring with the preceding species, from which 

 it differs in form and in its much wider umbilicus. 



N. CASTA, Phil. PI. 17, fig. 63. 



Whorls obliquely flattened above, angulated around the rather 

 wide umbilicus ; columellar callus moderate, entering the um- 

 bilicus ; white. Length, 1-5 inches. 



Hab. unknown. 



Distinguished from the other species of the group by the wide 

 umbilicus and sloping form of the body-whorl. 



N. ALBUMEN, Linn. PI. 20, fig. 5. 



Obliquely depressed, orange-brown ; umbilicus very wide, 

 bordered b} r an angle, white, with a strong central entering 

 callus. Length, 1-5-2 inches. 



Singapore, Moluccas, Philippines. 



X. COLUMNARIS, Rccluz. PI. 20, fig, 4. 



Widely globose, pure white, polished, base strongly angulated 

 around the very large umbilicus, which bears a slight spiral 

 ridge and is more or less filled by a strong, broad central enter- 

 ing callus. Length, 1/5-2 inches. 



Philippines, Mauritius. 



It is N. pes-elephantis, Chemn., and probably N. funiculata, 

 Reel. 



N. DUBIA, Recluz. PL 1C, fig. 50 ; PL 17, fig. 67 ; PL 18, fig. 73 ; 

 PL 19, fig. 94. 



Thick, with small spire and but slightly marked suture; white 

 under a slight yellowish white epidermis ; umbilicus narrow, 

 bounded by an almost cord-like angle, in the adult nearly filled 

 by an entering callus, at which place the columellar lip often is 

 cut into one or two mamillary callous deposits. 



Length, 1-25-1-75 inches. 



Chili, Peru. 



N. Atacamensis, Phil. (fig. 94), N. amiculata, Phil. (fig. 73), 

 and N. rapulum, Reeve (fig. 67), are S3'nonyms. 



N. CORA, d'Orb. PL 19, fig. 86 ; PL 16, fig. 58 ; PL 19, fig. 84. 



Shell thick, conical ovate, body-whorl obliquely flattened 

 above ; umbilicus narrow and deep, bounded by a ridge, partly 



