500 PROCEEDINGS OF THE INDIANA ACADEMY OF SCIENCE. 



more apt to have waterdogs on the hooks when examined in the morning than 

 when inspected in the evening. 



That the species is. however, not wholly nocturnal is shown by the fact 

 that individuals are often seen in day-time moving about on the bottom, 

 especially in winter under the ice, and the further fact that they are some- 

 times taken in the day-time by anglers or on set-lines. 



They also appear to be active throughout the year; there is no evidence 

 that they hibernate. We have observed them moving about and have caught 

 them at all seasons, practically in every month in the j^ear. 



Actually, we saw them most frequently in winter, probably not because 

 they were more abundant then or moving about more constantly, but because 

 they were less active in their movements and therefore more easily observed; 

 and especially because the presence of a sufficiently strong sheet of trans- 

 parent ice on the lake gives an ideal condition for observ^ation and study of 

 the lake bed even in considerable depths. 



As already stated, the waterdogs make shallow burrows in the soft bottom 

 or under the Chara mat, in which they make their homes. They are also found 

 under water-logged chunks or boards where they may be sometimes seen 

 with their heads shghtly e.xposed. Then again they may be observed now and 

 then among the roots of the pond-liUes or the denser patches of Potamogeton, 

 Myriophyllum and similar aquatics. 



In late autumn and early winter, when th(^ water lias cooled and the straw- 

 colored minnows, grayback minnows and skipjacks crowd to the shore, 

 waterdogs may l)e sometimes seen (coming in among them, evidently for the 

 puri)ose of preying upon the fishes. Later, during the winter, on bright 

 sunny days, these animals were frequently seen in some numbers crowded 

 close to sliore and lying motionless under the clear ice. Several were caught 

 by cutting holes through the ice above them. Occasionally one would take 

 alarm while the ice was being chopped away, and swim off, rather slowly 

 at first and then quite rapidly, with lateral flexions of the tail. Though not 

 so rapid in their movements in Avinter as in summer, they can swim quite 

 swiftly when occasion arises. When not frightened, if moving at all, they 

 walk along the bottom with great delil)eration, moving their heads from side 

 to side as if smelling their way along. In walking, diagonal hmbs are moved 

 in unison, that is, the right front with the left hind leg and the other two the 

 same way, with a good deal of circular or rotary motion at the hips and 

 shoulders like one turning a crank. When one is caught in the hand or when a 

 feint is made to take hold of one, it will make quick, vicious snaps at the hand. 

 The jaws are strong enough to make the bite painful. This quick snappy 

 motion offers a suggestion as to the manner in which the animal catches 

 fishes. 



The Waterdog seems to feed chiefly on small fishes and crawfishes. The 

 stomachs of several examined Decemb(!r 10, 1900, and later the same winter, 

 were Uterally packed with fishes. At various times in December one or more 



