22 PBELIMINAEY BEPOET 



Genus CARPIODES Eafinesque. 

 KE¥ TO THE SPECIES OF CARPIODES. 



A. Back not greatly elevated, depth about 3 in length; lips thin, the 



halves of the lower lip meeting at a wide angle. . . carpio, 7& 

 AA. Back considerably elevated, depth about 2i in length. 



B. Lips thin, silvery white in life, the halves of the lower lip 



meeting at a wide angle as in C. carpio. . . . difformis, 22 

 BB. Lips thick, reddish in life, the halves of the lower lip meet- 

 ing at an acute angle velifer 23- 



Carpiodes carpio (Eafinesque). Carp Sucker. 



Lower pharyngeal bones narrow, the teeth weak. Coloration, 

 light silvery, sometimes brassy, some scales occasionally brownish 

 at the base. Back compressed and not so much elevated as in the 

 preceding species; head rather short, contained 4 to 5 times in the 

 length of the body; first rays of the dorsal fin short, longest rays 

 f to 3-5 the length of the dorsal, never extended in long filaments, 

 thickened at the base so as to be quite stiff in the adult; front of 

 dorsal fin nearer the snout than the base of the caudal ; caudal fin 

 forked; snout a little longer than the width of the eye, not project- 

 ing far beyond the mouth. Eye 4^ to 5 in the head. Head 4 in 

 length. Depth 3. Dorsal fin with 25 to 80 rays. Scales 7-37-5. 



Many small specimens were taken in the Minnesota River at 

 Ortonville which are thought to be this species (Woolman & Oox^ 

 1892); a specimen in the University Museum was taken from the 

 Mississippi Eiver at Minneapolis (Nat. Hist. Surv., 1893). Further 

 collections wiU probably prove it to be common, especially in the 

 streams of the Mississippi system. 



Carpiodes difformis Cope. 



Snout very blunt, the front of the lower jaw about even with 

 the front of the eye socket, the maxillary bone extending back to 

 the anterior edge of the eye; nostrils inserted very near the tip 

 of the snout; eye large, contained 3^ to 4 times in the head. Lower 

 lip n -shaped below. Head contained in the length 4^ times. The 

 back considerably elevated and the depth less than half the length. 

 Scales 6-35-4. Dorsal fin very high and averaging 24 rays, its first 

 ray inserted nearer the snout than the base of the caudal fin. 



Not common in Minnesota and further study and collections 

 are needed to determine its distribution. Several small specimens 

 have been taken in the Blue Earth River at Mankato (Cox, 1892). 



