FISHES OF THE MISSOURI RIVER BASIN. 



301 



27. Catostomus griseus (Girard). Milk Eiver Suclcer. Sweetwater River (a. Catos- 

 tomus (Acomu,) griseus type, Girard, 1856 and 1858); Milk River (as Catos- 

 tomus (Acomus) lactarius type, Girard, 1856 and 1858) . Milk River, Mont, (as 

 Catostomus retropinnis type, Jordan, 1878); Horse Creek, Red Cloud Creek, 

 and Platte River (as C. griseum, Cope, 1871); South Platte River, Denver 

 and Ilartsel Hot Springs, Colo.; Rear Creek, Morrison, Colo.; Middle 

 Boulder Creek, Boulder, Colo. (Jordan, 1891); Yellowstone- and Gardiner 

 rivers (Jordan, 1891a); Missouri River, Craig, Mont. (Eigenmanu, 1894). 

 Two specimens were taken from the North Platte River at Douglas, 

 They give the following measurements : 



Total 

 length. 



J iifln , 



Head. 



Depth. 



Eye. 



Snout. 



Dorsal. 



Anal. 



Scales. 



15-88-10 

 15-95-10 



Compared with specimens of C. commersonii sucUxi of the same size, the 

 following differences are noted: Body rather heavier or stouter; caudal 

 peduncle shorter and deeper, the least depth being 2* in head, while in C. 

 commersonii sucUn it is more than 3; the top of the head is less arched 

 and the snout more prominent; the mouth is a little narrower and the lobes 

 of the lower lip are longer; the scales are very small, particularly on the 

 anterior part of the body; the color is much paler, the three dark spots 

 usually present on younger specimens of var. sucklii not being present on 

 qriseus at all. Compared with smaller specimens of C. catostomus, the dis- 

 tinguishing characters are found to be very slight. In C, griseus the top of 

 the°head is flatter and the snout is less decurved; the upper lip is larger 

 and more pendant, and has more papilla-; the lobes of the lower lip are 

 rather longer, and the cartilaginous sheath is less developed; the dorsal fin 

 is smaller, it having but 10 rays. 

 28 Catostomus catostomus (Forster). Long-nosed Sucker. This sucker was ob- 

 tained at the following places: North Platte River; Deer Greek, Glenrock ; 

 Clear Creek, Clermont; Powder River, Arvada; Big Goose Creek, Sheridan, 

 and south fork of Tongue River, Sheridan. It was not found anywhere m 

 Nebraska or South Dakota, and probably does not occur in the Missouri 

 Basin east of Wyoming. It was obtained in 1892 by Dr. Eigenmann in the 

 Red River of the North at Winnipeg, Swift Current Creek, and Bow, Elbow, 

 Vermillion, and Saskatchewan rivers, all in the Saskatchewan Basin. The 

 important characters of the larger specimens collected by us are given in 

 the following table : 



Locality. 



Arvada, "Wyo... 

 Sheridan, Wyo.. 

 Clermont, Wyo. 



Do 



Douglas, Wyo... 

 Sheridan, wyo 



Do 



Do 



Total 



length Bead in 



in length. 



inches 



7i 



7 

 11 



Depth 



in 

 length. 



4 



4 



4? 



Eye 

 in 



head. 



Eye 



in 



snout 



The Sheridan specimens are badly decayed and accurate measurements can 

 not bo taken. In all of these specimens the scales are considerably smaller 

 than the examples of C. griseus from Douglas, the top of the head is more 

 curved, and the snout less prominent. The upper lip is incised nearly to the 

 base, there being but a single row of papilhe across the base. 



