12 MANUAL OF THE MOLLUSCA. 



Type, E. spirata. PL V., fig. 11. 



Shell umbilicated when young ; inner lip callous, spreading and covering 

 the umbilicus of the adult ; operculum pointed, nucleus apical. 



Distr., 9 sp. Red Sea, India, Cape, Japan, China, Australia. Solid, 

 smooth shells, which have usually lost their epidermis, and are pure white, 

 spotted with dark red ; the animal is spotted like the shell. 14 fois. (Adams.) 



NASSA, Lam. Dog-whelk. 



Etym., nassa, a basket used for catching fish. 



Syn., desmoulinsia and northia, Gray. 



Type, N. arcularia. PL V., fig. 15. 



Shell like buccinum ; columellar lip callous, expanded, forming a tooth- 

 like projection near the anterior canal. Operc. ovate, nucleus apical. Lingual 

 teeth arched, pectinated ; uncini, with a basal tooth. 



The animal has a broad foot, with diverging horns in front, and two little 

 tails behind. N. obsoleta (Say) lives within the influence of fresh water and 

 becomes eroded. N. reticulata, L., is common on the English shores, at 

 low-water, and is called the dog-whelk by fishermen. 



Distr., 68 sp. Low-water 50 fms. World-wide. Arctic, Tropical and 

 Antarctic Seas. 



Fossil, 19 sp. Eocene . Brit., &c., N. America. 



Sub-genus, cyllene, Gray. C. Oweni, PL V., fig. 17. Outer lip with a 

 slight sinus near the canal ; sutures channelled. W. Africa, Sooloo Islands, 

 Borneo. Fossil, Miocene, Touraine. 



Cyclonassa, Swainson. C. neritea, PL V., fig. 16. 



PHOS, Montfort. 



Etym., pkos, light, Syn., rhinodomus, Sw. 



Type, P. senticosus, PL V., fig. 18. 



Shell like nassa ; cancellated ; outer lip striated internally, with a slight 

 sinus near the canal ; columella obliquely grooved. 



The animal has slender tentacles, with the eyes near their tips. 



Distr., 30 sp. (Cuming.) Red Sea, Ceylon, Philippines, Australia, 

 W. America. 



? RINGICULA, Deshayes. 



Etym., diminutive of ringens, from ringo, to grin. 

 Type, R. riugens, PL V,, fig. 21. 



Shell minute, ventricose, with a small spire ; aperture notched, columella 

 callous, deeply plaited ; outer lip thickened and reflected. 

 Distr., 4 sp. ? Medit., India, Philippines, Gallapagos. 

 Fossil, 9 sp., Miocene . Brit., Trance. Rinyicula is placed with nassa 



