112 POPULAR CONCHOLOGY. 



ligament partly internal. Animal, foot thin 

 and cylindrical. — 38 species recent, and 9 fossil. 



The Mytilus or Mussel is found in most parts 

 of the world, and is abundant on rocky coasts, 

 where it is met with, attached by its byssus so 

 as to be covered at high tide: an instance is 

 known of a lobster having been found covered 

 with them. When the shell of the common 

 English species, the Mytilus edulis, is freed 

 from its epidermis and polished, it is of a beau- 

 tiful deep purple colour ; the animal is much 

 sought after as an article of food, and, although 

 not equal to the oyster, makes a palatable dish ; 

 but care is necessary, as it is often unwhole- 

 some. Frequently towards the end of autumn, 

 small crabs are found in the shell of the Myti- 

 lus, which live there sheltered from danger 

 without hurting the inhabitant. Small seed 

 pearls are sometimes found in this species. 

 One or two species are found in fresh water, 

 the Danube, the Wolga, and Rhine, the London 

 Docks, &c. &c. A new generic name, Dris- 

 sena, has been given to them by M. Vanbene- 

 den, but it has not been universally adopted. 

 71. Pinna. Shell equi valve, rather trian- 



