INDEX. 



SYSTEMATICALLY ARRANGED. 



SECOND GREAT DIVISION OF THE ANIMAL KINDGOM. 

 ANIMALIA MOLLUSCA. 

 General Characters of the Division, 1. 

 Division of Mollusca into Classes, 4. 



CLASSES. 



I. Cephalopoda. 

 II. Pteropoda. 

 III. Gasteropoda. 



IV. ACEPHALA. 



V. Brachiopoda. 



VI. CiRRHOPODA. 



ORDERS, GENERA, AND OTHER DIVISIONS. 



CLASS I.— CEPHALOPODA. 



Sepia, 7 



Octopus, 7 



Polypus of Aristotle, 9 

 Eledon of Aristotle, 10 

 Argonauta, 10 

 Bellerophon, 11 

 Loligo, 1 1 



Loligopsis, 12 

 Loligo proper, 12 

 Onychotheuthis, 1 1 

 Sepiola, 12 

 Chondrosepia, 12 

 Sepia proper, 12 

 Nautilus, 13 



Spirula. 13 

 Nautilus proper, 14 

 Lituus, 14 

 Belemnites, 15 

 Actinocaraax, 15 



