FISHES OF PENNSYLVANIA. 21 

ORDER EVENTOGNATHI. 
Famity CATOSTOMIDA. Tue Suckers. 
Genus ICTIOBUS Rarinesgue. Burrato FisHes. 
24. Ictiobus urus Aaassiz. 
The Big mouthed Buffalo Fish. (Figure 27. 
The big-mouthed buffalo fish has a stout body and head, the back elevated, and a 
large mouth. The depth of the body is equal to one-third of the total length with- 
out tail. The head is contained three and one-fourth times in the standard length. 
The eye is of moderate size, its length about one-sixth that of the head. Mucus 
pores well developed. The mouth is somewhat oblique; the maxillary not reach- 
ing vertical through eye. The caudal peduncle is broad, its least depth almost half 
length of head. The rather long dorsal fin commences on middle of body, the length 
of its base equal to depth of body; the anterior rays high, longest half length of 
dorsal base ; beginning with the ninth the rays are about of equal length, and not 
much more than one-third length of longest rays. 
Caudal forked. Pectoral moderate, its length about equal to that of longest dor- 
sal rays. The anal is short, its base equal to one-half the length of its longest ray, 
which equals longest dorsal ray. D. 25 or 26; A. 8or9. Scales, 7-36-6, large and 
striated. Lateral line complete and straight. The specimen described, No. 35,882, 
United States National Museum, from the Missouri river, is fourteen inches long. 
The black buffalo, big-mouthed buffalo or mongrel buffalo of authors, 
occurs in the Mississippi and Ohio valleys, but is less abundant than the 
other species of the genus. It grows to a length of two and one-half 
feet, and is extensively used for food. The species is found only in the 
larger streams, and is distinguished from all the other buffalo fishes by 
its darker colors, as well as by its large mouth and stout body. 
25. Ictiobus bubalus (Rarinesque). 
The Red-mouthed Buffalo Fish. 
The red-mouthed buffalo fish has the back elevated, body robust more or less com- 
pressed, mouth terminal with little developed lips, opercle very large and strong, 
large scales and a long, .ow, dorsal fin. The depth of the body equals one-third of 
its length; the length of the head is contained three and one-half times in the stand- 
ard length ; the dorsal base two and two-thirds in the same length. Diameter of eye 
equals about one-seventh length of the head. Teeth small and numerous. D. 29; 
A. 9; V.10. Scales7-44-6. The example described, No. 20,774, United States National 
Museum, from Illinois, is eighteen inches long. 
The red-mouthed buffalo fish, also known as the brown buffalo, high- 
backed buffalo, small-mouthed buffalo, sucker-mouthed buffalo and buffalo 
fish, is a common inhabitant of the Mississippi and Ohio valleys, but 
does not occur east of the Alleghenies. 
This species reaches a length of two and one-half feet and a weight of 
fifteen pounds. It frequents large streams. Prof. Forbes has been in- 
formed by fishermen that one or more species of buffalo fish have the 
