92 



BRANCH VERTEBRATA. 



ORDER CHONDROSTEI (kon dros'te I). 



The Sturgeon has the body protected by five rows of 

 large bony plates. Its snout reaching in front of the 

 mouth is flattened and has four flexible filaments ex- 

 tending from its lower surface. These are seemingly 

 feelers to recognize its food half concealed in the mud, 



FIG. 158. 



Aciperiser slu'rid. Sturgeon. 



and which is readily seized by its protrudable mouth. 

 Seven different species are found in the coast and interior 

 waters of the United States, varying in weight from a 

 hundred to six hundred pounds. The smaller species in- 

 habit the Mississippi and the great lakes. Acipenser 

 sturio (asipen'ser stu'rl o) is found on both sides of the 

 Atlantic, sometimes attaining on the European coast a 

 length of eighteen feet. 



ORDER GINGLYMODI (ging glT mo'dl). 



The Gar-pikes are represented by three or four species, 

 one of which, the Osseus (6s' se us), is widely distributed 

 in lakes and rivers throughout the United States. Its 

 enameled rhomboid scales in oblique series, its long and 

 slender form, and its projecting upper jaw are character- 

 istics, by which it is readily distinguished from all other 



