464 



COLLEGE ZOOLOGY 



It is long and slender, and its scales are inconspicuous. The 

 dorsal, caudal, and anal fins are continuous. The eels enter the 

 sea in the autumn to spawn, after which they die. The .eggs are 

 deposited on mud-banks usually near the mouths of rivers. The 

 young develop in the sea and then migrate up the rivers. Eels 

 are considered by many a good article of food, and are therefore 

 of commercial value. 



Family Gasterosteid^e. — The Sticklebacks. These are 

 small fishes famous for their nest-building habits. The common 



Fig. 3g6. — The two-spined stickleback, Gasterosieus 

 bispinosus. Above, nest with eggs, and male entering. 

 Below, male depositing its milt on the eggs. (From 

 Davenport.) 



Eastern stickleback, Gasterosieus bispinosus (Fig. 396), has two 

 large spines preceding the dorsal fin. The nest is built of sticks 



