202 
BULLETIN OP THE BUREAU OF FISHERIES 
dam, the Des Moines River, and more abundantly in Sugar Creek. Some small specimens are slen- 
der enough to be called N. whipplii but are assumed to be of the same species as the larger examples. 
Phenacobius mirabilis (Girard), sucker-mouthed minnow: Sugar Creek, about 2.5 kilometers 
from its mouth, March 22, 1916. The largest measured 7.7 centimeters (3 inches) over all and con- 
tained an earthworm in its stomach. 
Hybopsis hyostomus (Gilbert): Mississippi River at Keokuk, September 2, 1915, May 25 and 
June 7, 1916 (3). 
Hybopsis storerianus (Kirkland), Storer’s chub: Several collected in the river (identification 
confirmed by Lewis Radcliffe); one example, 10.8 centimeters total length, taken from stomach of 
a goujon, April 24, 1915; Sugar Creek, March 21, 1916 (small, identified by Dr. W. C. Kendall); 
Mississippi River, May 19, 1916 (1). 
Hybopsis kentuckiensis (Rafinesque), river chub, horny-head: Sugar Creek, March 21, 1916 (4, 
identified by Dr. W. C. Kendall). 
THE SUNFISHES AND BLACK BASSES (Centrarchidee) 
The keenest interest of nearly all persons except commercial fishermen and mar- 
ket men is, of course, in the game fish, which are included chiefly in this and the follow- 
Figure 25. — Largemouth black bass, Micropterus salmoides 
ing family; but, for reasons that will readily be understood when given, we have the 
fewest notes of direct observations to submit in reference to these fish. The natural 
histories of the game fishes are relatively so well known that it seemed inadvisable to 
give special attention to their study, except in so far as certain specific questions relating 
to the dam were involved. There were just two leading questions : First, does the dam 
as an obstruction act as an injurious barrier to upstream movements of game fish; and, 
second, does the lake offer them a favorable or unfavorable environment? The obser- 
vations bearing upon the forpier question were negative and therefore are stated 
briefly. As to the second question, quantitative data are difficult or impossible 
to secure because of the general mode of taking game fish, while an effective answer 
to the question in terms of common information seems so clear as to admit of brief 
presentation. 
The species of this family that are chiefly involved are the following: The white 
crappie, Pomoxis annularis (Rafinesque) ; the less common black crappie, P. sparoides 
(Lacepede) ; the bluegill or blue bream, Lepomis incisor (Mitchill) ; and the large- 
mouth black bass, Micropterus salmoides (Lacdpede). The white crappie was appar- 
ently about three times as abundant as the black crappie. The common sunfish of the 
region, large enough for table use, were practically all bluegill. Other species were 
