226 



BUI^LETIN OF THE BUREAU OF FISHERIES. 



on the map) on September 20, 191 1. One hundred and ninety-three individuals about 

 1^ inches long were taken on stony shoals on the west side of the entrance to North 

 Fishtail Bay on September 18 of the same year. With them were three Notropis 

 cayuga and four N. hudsonius. A few were taken in August in company with large 

 numbers of A^. hudsonius on the sand shoals of South Fishtail Baj'. In life they 

 are distinguishable from .'V. hudsonius by the following field characters: (o) Darker 

 color; (ft) a peculiar jerky movement in progression. The fish do not move directly 

 ahead, but by a flick of the tail and of the pectorals the head is jerked to one side and 

 then to the other or several times to one side and several times to the other, so that the 

 course is zigzag; (c) the body is semitranslucent, so that the vertebral column and the 

 viscera may be seen faintly from the back; (d) the scales in front of the dorsal on 

 the back are crowded so as to appear much smaller than the scales behind them. 



/o 



/S 

 Ounces 



20 



JSS 



so 



Fig. 2. — Graph showing the relation of length and weight for the 14 common suckers, Catosiomus commersonii, included 

 in table i. Each space on the horizontal line represents i ounce; each space on the vertical line i inch. Curve 

 drawn free-hand. 



We have collected this species in numbers only on or verj' near stony shoals and 

 in the neighborhood of protected bays. Stony shoals afford it breeding grounds, for 

 it lays its eggs beneath flat stones and similar objects on the bottom, and the mucky 

 bottom of protected bays affords it food, for it is a "mud eater." It has been taken but 

 rarely and in small numbers on the sand shoals along the south and west shores of South 

 Fishtail Bay, although frequent collections have been made there. These wave-swept 

 shoals afford neither stones nor muck. 



SemoTilus atromaculatus (Mitchill), horned dace, or creek chub, has been taken 

 only in the vicinity of Bryant's dock (locaUty 9). Here the adult was found in consider- 

 able numbers in company with Pimephales nolatus and A^ hudsonius. It is abundant 

 in Maple River near the lake. Bryant's is a resort of fishermen. It is possible that the 

 homed dace has been introduced here as a bait fish and has not extended its range to other 



