INTERDUNAL PONDS AND TAMARACK SWAMPS 175 



twenty-two or twenty-three rays in the anal fin, including rudi- 

 mentary ones. It reaches 18 inches in length, though it is usually 

 much smaller. The color is dark yellow-brown to black above, 

 usually mottled; below 

 it is gray, pink, or 

 white. The lower 

 barbels are similarly 

 colored. The black 

 bullhead is found in 

 the older ponds. 



The tadpole cat 



FIG. 191. Golden shiner, Abramis crysoleucas, 



reduced one-half. 



(Fig. 194) is a small 

 fish, 3-5 inches long, 

 with a thick, fleshy head, so it does have something the shape 

 of a tadpole. It is dark olivaceous above, yellow below. The 

 dorsal fin has a spine at its forward edge, which is more than 



half the height of the fin. 



The chara in the un- 

 drained ponds, as well as 

 those in connection with the 

 lake, swarms with the blood- 

 red larvae of Chironomus, a 

 midge. These bloodworms 

 crawl upon the plant and 

 build tubes -in which they 

 conceal themselves in part. 

 A new caddis-fly larva (Lep- 

 tocera) that builds a long, 

 slender tube of tiny sand 

 grains, replaces the one that 

 was common in the more open chara beds. In the deeper parts 

 of the chara, red water mites, Limnochares aquaticus are abun- 

 dant. Some small snails (Amnicola limosa and A. cincinnatien- 

 sis) are found creeping upon the plants on which larger snails are 

 also frequently present, namely, Physa gyrina, known by the 



FIG. 192. Head of chub sucker, Erimy- 

 zon sucetta. 



