l CONTENTS OF VOL. II. 



Page. 



A. Aperture of the shell entire. 



1. Aperture of the shell closed by a lid. Turbonidae. 



Neritadse. Trochusidae. . 488 



2. Aperture of the shell exposed. Janthina. Velutina. 489 



B. Anterior margin of the aperture of the shell canali- 

 culated. 



1. Shell convoluted. Cypreadae. Ovuladae. Volu- 

 tadae, . 4QO 



2. Shell turreted. Buccinidae. Muricidae. Cerithiadae. 



Strombusidae. 491 



Tribe II. 

 Shell internal. Sigaretus. . ib. 



Subdivision II. 



Heart traversed by the rectum. 



Tribe I. Shell ear-shaped. 



Haliotidae, Haliotis, Padola, Stomatia. 492 



Tribe II. Shell conical. 



Crepiduladse. Capulusidae. Fissurelladae. 494 



Division II. Mollusca Acephala. 



Section I. ACEPHALA CONCHIFEHA. 

 Order I. BRACHIOPODA. 



Subdivision I. 



Shell supported on a fleshy peduncle. 



Lingula. Terebratula. . 496 



Subdivision II. 



Shell sessile. Criopus. 499 



Order II. BIVALVIA. 



Description. Ligament. Muscles. Syphons. Byssus. 



Foot Crystalline process. Pearl, . 499 



