622 Lake Maxinkuckee, Physical and Biological Survey 



on the bottom, especially in winter under the ice, and the further 

 fact that they are sometimes taken in the daytime 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 year. 



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 transparent ice on the 

 lake gives an ideal condition for observation and study of the lake 

 bed even in considerable depths. 



As already stated, the water-dogs 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 slightly ex- 

 posed. Then again they may be observed now and then among 

 the roots of the pond-lilies or the denser patches of Potamogeton, 

 Myriophyllum and similar aquatics. 



In late autumn and early winter, when the water has cooled, 

 and the straw-colored minnows, grayback minnows and skipjacks 

 crowd to the shore, water-dogs may be sometimes seen coming in 

 among them, evidently for the purpose of preying upon the fishes. 

 Later, during the winter, on bright sunny days, these animals were 

 frequently seen in some numbers crowded close to shore 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 winter as in sum- 

 mer, they can swim quite swiftly when occasion arises. When not 

 frightened, if moving at all, they walk along the bottom with great 

 deliberation, moving their heads from side to side as if smelling 

 their way along. In walking, diagonal limbs 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. 



