CLASSIFICATION. 



LlNNiEUS ranks Testacea as the third order, in his 

 sixth class of animals called Wonns. He has made three 

 principal or grand divisions, viz. 



MULTIVALVES, BIVALVES, AND UNIVALVES. 



The latter division he has subdivided, as will be seen 



in the sequel. It may be proper to acquaint the reader, 



that, throughout this work, his system has been adopted. 



TESTACEA. 



MOLLUSCA COVERED WITH A SHELL. 



I. MULTIVALVES. 



Shells with many Valves. 

 1. Chiton : Valves placed in transverse plaits down the 



back. 

 "2. Lepas: Valves unequal; body sesile. 

 3. Pholas : Shell bivalve, with accessory valves at the 



hinge. 



