CLASS GASTROPODA 
55 
armed with white ridges within, in the young shell, which afterward 
develop strong teeth at the end, and are last of all absorbed; and the thin 
inner lip, which develops one strong transverse parietal plate between two 
small denticles (others being just discernible in the young shell), and one 
large slanting columella fold, which winds round the base of the pillar, 
making an umbilical chink. A few extremely faint spiral striae are some¬ 
times seen on the epidermis, near the base and above the bluntly-angled 
shoulder. Long., .65; long, spire, .11; latitude, .38 inch. (Carpenter.) 
Type in Liverpool Collection. Type locality, Mazatlan, Mexico. 
Range. Monterey Bay, California, to Mazatlan, Mexico. 
Family GADINIIDAE 
Genus GADINIA (Adanson) Gray, 1824 
Shell depressedly-conical, surface radiated; apex subcentral, or a little 
posterior; aperture wide, expanded, muscular impression horseshoe¬ 
shaped, the right side shortest, terminating at the siphonal groove; 
siphonal groove in the front of the right side of the muscular scar. 
Type. Gadinia peruviana Gray. 
Distribution. Mediterranean, Red Sea, Africa, Peru, west coast of 
North America. Fossil: Sicily. 
The animals of this genus have very similar habits to those of the 
Patellidae. Adanson, who first observed them living on the rocks of the 
Island of Goree and of Cape Manuel, named them “Gadin.” 
Synonym Mouretia Sowerby, 1834. Lyria Gray. Clypeus Scacchi, not 
Klein. Rowellia Cooper, 1865. 
Gadinia reticulata Sowerby, 1835 
Plate 2, figs. 16a, b 
Proceedings, Zoological Society of London, 6. American Journal of Conchology, 6: 
Pis. 2, 4, 1870. 
T. testa supdepresso-conina, subrotundata, subterne reticulata, alba. 
(Sowerby.) 
Shell normally almost circular; depressed conical; white or livid, some¬ 
times tinged by the growth of a green or pink nullipore. The upper 
surface marked with from thirty to fifty radiating striae or riblets which 
are reticulated by the coarse, somewhat elevated lines of growth. The 
margin in young shells is denticulated, but with age this character is lost. 
[ 55 ] 
