22 FISHES OF PENNSYLVANIA. 



“pecular habit of whirling around in shallow water or plowing steadily 
along, with their heads buried in the mud, and their tails occasionally 
showing above the surface. These operations have nothing to do with 
spawning, and it is likely that fishes thus engaged are burrowing for 
small mollusks and for mud-inhabiting larvee.” The food of this buffalo 
fish consists of aquatic plants, in the Illinois river chiefly duck weed and 
Ceratophyllum. The animal food includes mollusks, insects and their 
larvee and crustaceans. Worms are rarely found in their stomachs. The 
buffalo is not a choice fish and its flesh is filled with innumerable small 
bones, yet it is abundant and is eaten in very large quantities. These 
fish do not take the hook and are usually caught in seines. 
26. Ictiobus carpio Rarinesqvez. 
The Carp Sucker. (igure 28.) 
The body of the carp sucker is fusiform, back little elevated and sides compressed. 
The depth of the body at the origin of the dorsal is contained about three and one-fourth 
timesin the length without caudal,the length of the head three and three-fourths times, 
Muzzle more or less conic, rounded on top; mouth small, horizontal and inferior, with 
thin lips. Muciferous system on head moderately developed. Theeye is of moderate 
size, its diameter contained five timesin length of head. The distance from tip ofsnout 
to origin of dorsal equals nearly one-half the distance from tip of snout to caudal base. 
First and second rays of dorsal partly ossified, first very small, one-third as long as 
the second which is less than one-half as long as the third or longest ray, which is 
slightly more than one-half dorsal base. The rays gradually decrease in length from 
the third to the tenth, which is contained three and one-half times in the third, and 
are of equal size from this ray back. The pectorals are placed low; ventrals with a 
broad base and caudal well forked. The scales are large and about equal in size all 
over the body. D. 28 (to 30); A. 8; V. 10. Scales 7-37-6. The lateral line is well 
marked and slightly decurved. 
Deseribed from No. 36,509, United States National Museum, nine and one-half 
inches long, from the Rio Colorado, Texas. 
The big carp sucker or olive sucker is an inhabitant of the Ohio and 
Mississippi valleys. It is a common species and grows toa moderately 
large size, reaching eighteen inches in length, and is the largest of the 
carp suckers. In the Ohio river and its tributaries it is one of the most 
abundant fishes. In the Mississippi valley itsrange extends southward 
to Texas. The species has not been recorded from Lake Erie. 
The food of the carp sucker is similar to that of other species of the 
genus. It includes soft-shelled mollusks, small crustaceans, worms and 
aquatic plants. 
Although this is not a choice fish it is extensively used for food. 
27. Ictiobus difformis (Cope). 
The Deformed Carp Sucker. 
This species is fusiform, sides compressed, back much elevated, the head conic, 
rounded on top, with very blunt muzzle. The eye is longer than the snout, one- 
fourth length of head. Mouth small, horizontal. The greatest depth of the body 1s 
at the origin of the dorsal and is contained twoand two-thirds times in the totallength 
without caudal; length of head four and one-fourth times. Anterior rays of dorsal 
