GASTEROPODA CONSIDERED AS A CLASS. 403 

 FIG. 546. 



Teeth of S trombus, Welton. 

 FIG. 547. 



FIG. 548. 



Teeth of Murex tenuispina, Welton. 



One of the most curious parts of these animals is the 

 tongue, or lingual ribbon, which is a band armed with a 

 great number of glossy siliceous 

 teeth, which are arranged in 

 rows in the most regular man- 

 ner; and differently in the differ- 

 ent kinds of gasteropods. The 

 tongue of some kinds contains 

 one hundred and sixty rows of 

 teeth, and one hundred and 

 eighty teeth in each row, or more 

 than twenty-eight thousand in 

 all! 



Many of the Gasteropods feed 

 upon vegetable substances, and 

 these generally have the aperture 

 of the shell entire. The others portion of Tongue of the 

 feed upon animal substances, and *** ^datum. Magnified. 



