306 SNAILS. 



these singular creatures may sometimes be observed in 

 the act of diverting themselves, by sailing or rowing 

 about in this manner. But, on the least alarm, they 

 withdraw themselves, and sink to the bottom. In the 

 early ages of the world, it has been conjectured that 

 mankind were furnished by these animals, with the 

 original idea of navigation. 



The COWRIES are a very numerous tribe, and their shells 

 have the utmost brilliancy and elegance, bearing some 

 resemblance even to porcelain. Some of them are very 

 large, and others diminutively small. They are found 

 on the sand at the bottom of the sea, and are chiefly 

 natives of hot climates. In shape they are generally oval, 

 and have a narrow opening, which extends from one end 

 to the other. Each animal is said to quit its shell after 

 possessing it a year, and to form a new one. One kind, 

 called the Money Cowry, are found on the sea-coasts of 

 Africa and the East Indies, in which countries they are 

 used as money ; but their value is extremely small, two 

 thousand of them being only equal to our half-crown. 



SNAILS are common in all countries. Some of the 

 species are inhabitants of the land, others of fresh waters, 

 and others of the sea : some of the smaller kinds are found 

 on the trunks of trees. They feed principally on vegeta- 

 ble productions, and many of them have been known to 

 continue for months, and even years, without food, and 

 yet to survive so long a fast. They possess also a very 

 considerable degree of reproductive power ; for even if 

 their head be cutoff, it will, in many instances, grow 

 again. Most of them lay eggs about the beginning of 

 summer, but a few produce living young ones. They 

 have on the upper part of their head, four tentacula, 



