138 PAPERS ON ZOOLOGY OF MICHIGAN. 



covered with humus in depressions or about plant growths. The depth 

 is mostly less than two feet, but very irregular, with many shoals and 

 pools, some five or more feet deep. Wading could be done, however^ 

 almost everywhere. The water was cold (63° F. on the day when the 

 examinations of this part of the stream were made), and almost every- 

 where with a good current, but there are no rapids. Water plants were 

 abundant in the swifter parts of the stream, forming oblong patches; 

 the principal ones of these were tape grass, stoneworts, or slender- 

 leaved pondweeds, and Vaticheria, the latter forming bottom mats or 

 tufts. 



Sponges {Myenia fluviatilis) were found, and crayfish {Camharus 

 propinquus and C. virilis) were caught. Water insects were usually 

 in evidence. On the surface, were many water-striders and whirl-i-gig 

 beetles {Gyrinus ventralis and G. canadensis). Beneath the surface, 

 black-fly larvae were abundant on the leaves of tape grass, and some 

 dragon-fly and May-fly larvae and caddice-worms were caught. Small 

 bugs (Arctocorisa niiida) were taken in quantities in the seine. A few 

 snails (Physa gyrina) were collected. 



Small tadpoles were seen on quiet marginal shoals. Frogs and 

 small toads {Bufo ainericanus) were frequently seen along the shore of 

 the stream. Kingfishers were absent, which may have been due to 

 the scarcity of small fish. Some beaver work was noted, but these 

 mammals probably influenced the meager fish fauna of the river to a 

 very slight degree. All conditions appeared to be favorable for a large 

 fish fauna, but nevertheless fish were surprisingly few both as species 

 and individuals. This part of the river looked like a fine trout stream 

 but no trout were found in it by the writer or anyone else, according to 

 good testimony. Brook trout are in the south fork of Shelldrake 

 River, according to information received; and they have been planted 

 there but apparently not elsewhere in the river. The following species 

 of fish were caught in Shelldrake River: common sculpin, long-nosed 

 dace, common pike, common sucker, Cayuga minnow, common perch, 

 and long-eared sunfish (?). 



The first three species are apparently the only ones at all generally 

 distributed in the part of the stream examined, and sculpins are much 

 more common than the others. A number of long-nosed dace were 

 caught, but they were all very small. These, with the sculpins, were 

 taken in the masses of stoneworts, tape grass and pondweeds that grow 

 in the swift parts of the stream. The presence of so many sculpins 

 may be an important factor in keeping trout from the stream for they 

 are well-knowoi destroyers of trout eggs. One sculpin opened had been 

 eating a large burrowing May-fly larva and some other insects. Small 

 pike were frequently seen along the quiet margins. A sculpin two 



