CLASS PISCES 



455 



and the Mississippi Valley. The body is about a foot and one 

 half long, is dark olive in color, and bears, in the male, a black spot 

 at the base of the caudal fin. It is very voracious, feeding on fish, 

 crayfishes, mollusks, and other aquatic animals. The breeding 

 season is in April, May, or June, according to the latitude. The 

 male clears a space in the vegetation of a quiet inlet in which 

 the eggs are laid, and then guards the nest (Fig. 384) during 



Fig. 384. — The fresh-water dogfish or bowfin, Amia (Amiatus) calva, and 

 its nest. (From the Cambridge Natural History, after Dean.) 



the hatching period of from eight to ten days, and while the 

 young remain in the nest — about nine days more. The male 

 accompanies the young when they leave the nest, and con- 

 tinues to guard them until they reach a length of about four 

 inches. 



Order 4. Teleostei. — This order contains the majority of 

 living species, the bony fishes. The skeleton is extensively 

 ossified; the tail is usually homocercal (Fig. 377, B); and the 

 scales are cycloid or ctenoid (Fig. 371). Space will allow a 

 few notes on only about one eighth of the families of fishes 

 included in the order. 



