ORDER HETEROPODA. 15 



are produced in the water, the tribes that inhabit that 

 element, exceeding by far those that are to be found 

 upon the land. 



The Molluscous animals have been separated into the 

 five following Orders: — 



1. Heteropoda, (ivitJi feet, or organs of motion, 7iot iiniforni in 



all species.) 



2. Cephalopoda, (icitli feet, or organs of motion, attached to 



the head.) 



3. Trachelifoda, (with feet, or organs of motion, attached tothe 



neck, near tlie gills.) 



4. Gasteropoda, (with feet, or organs of motion, attached to the 



stomach.) 



5. Pteuopoda, (with feet, or organs of motion, like wings.) 



ORDER HETEROPODA. 



The creatures belonging to this order, says Lamarck 

 may be considered as the first vestiges of the appearance 

 of a series of marine animals, intermediate ifi their for- 

 mation between the fishes and the Cephalopods; they 

 are all natives of hot climates, and possess a body of a 

 jelly-like substance, and so transparent as to be seen 

 with difficulty when floating in the water. They do not 

 all possess shells, and are 4ess known than they other- 

 wise would be, on account of the great difficulty there is 

 in preserving them. 



The Glassy CarinariA, (Carinaria vitrea.) 



This singular animal is rarely taken, on account of 

 its delicate and perishable substance ; it is found in the 

 Southern Ocean. It will be seen, on referring to the 

 engraving, that the shell which it bears merely covers a 



