248 



ZOOLOGY 



The garpikes are known by their long snout (Fig 232). 

 They are completely clad in an enamel coat of mail. They 

 are of sluggish habits, but voracious, and their flesh is 



FIG. 232. Lepidosteus, the garpike. One-eighth nat. size. After Teimey. 



valueless as food. One species is found in China, the 

 others in the rivers of North America. 



The bowfin (Amia 1 ) occurs in the rivers and lakes of 

 the United States. It has a short body, a blunt head, and 



FIG. 233. Amia calva, the howtiii. One-sixth nat. size. From Leuuis. 



a long, dorsal fin (Fig. 233). It is the sole survivor of a 

 formerly large family. 



The Dipnoi 2 include only three rare foreign forms, which 

 seem to form a transition between fishes and the higher 

 groups, for some of them have lungs in addition to gills. 

 From some such lunged fishes must the amphibia have 

 arisen (Fig. 234). 



Ancestry of Vertebrates. - The fishes, amphibia, reptiles, 

 birds, and mammals, which are considered in this and the 

 following chapters, constitute together the group of verte- 

 brata, or backboned animals. All the animals treated of 



1 dut'a, ancient name of a fish. 



2 si 



Si's, twice ; irvo-fj, breath. 



