436 THE OCEAN WORLD. 
white spots, which is very common on the shores of the Medi- 
terranean. : : 
The eighth family is Weritide, of which we may give as typical 
genera, Weritina, Navicella, and Nerita. The species of Werita are 
numerous and pretty, and are mostly marine. 
~ a 
Fig. 231.—Monodonta labia (Lamarck). Fig. 232.—Delphinula spherula (Kiener). 
- The ninth family, 7urbinide, has among its more important genera 
those of Zurbo, Phasianella, Trochus, Delphinula, and Imperator. Of 
Delphinula only about seventy living species are known. They are 
Fig. 233.—Imperator stella (Lamarck). Fig. 234.—Trochus stellaris (Gmel). :, 
mostly natives of the Indian Ocean, and are remarkable for their 
numerous spines and the asperity of their shells (Fig. 232). Of the. 
genus /mperator we may instance the Spurred Trochus, /mperator 
stella, which is studded with radiating spines (Fig. 233), Zmperator. 
stellaris (Fig. 234), they are natives of the Australian seas, and 
Imperator imperialis, commonly called the Royal Spur. 
Our tenth family, Zzttorinide, contains the genera Solarium, 
