REPORT UPON THE FISHES OF IOWA. 
245 
DRAINAGE OF THE MISSOURI RIVER. 
I.— THE MISSOURI RIVER. 
The Missouri River at Sioux City is wide and shallow, with a rapid current, the 
bottom being composed of shifting quicksand. There ar« also many islands at this 
point, some composed of hard and others of soft materials. The water has a whitish 
or creamy tint, due to the fine silt held in suspension. The fishes when taken from 
the river have a pale or sickly appearance, but if placed for a time in clear water they 
assume their normal colors. The seining was done close by some islands, near the 
mouth of the Big Sioux River. 
FISHES OF THE MISSOURI RIVER. 
1. Polyodon spathula (Walbaum). Paddle-fiisli; Spoon-bill; Duck-billed cat. One specimen of this 
species is preserved in the agricultural college at Ames, Iowa. It was taken from the 
Missouri River in Harrison County, by E. G. Taylor, of Logan, Iowa. Specimens are 
occasionally caught near Sioux City, 
2. Scaphirhynchus platyrhinchus (Rafinesque). Sliovel-nosed sturgeon. Common. 
3. Ictalurus punctatus (Rafinesque). Channel cat; White cat; Silver cat. Common. 
4. Nocturus flavus (Rafinesque). Stone cat. Common. Anal rays, 15; head, 4; depth, 6f; width 
of head, 4£. 
5. Carpiodes velifer (Rafinesque). Quillback; Carp sucker. Rare. 
6. Hybognathus nu.chalis Agassiz. Silvery minnow. 
\ 7. Notropis dilectus (Girard). Emerald minnow. Rare. The specimens secured in this locality 
were small and differed somewhat from those obtained elsewhere in the State. The first 
dorsal ray is midway between the nostril and the base of the caudal. Diameter of eye very 
large, 3 in the head; snout short, two-thirds diameter of the eye; body more compressed 
than usual in this species; scales 37, about 28 scales before the dorsal; head, 4-J; depth, 4f ; 
color, bright olivaceous with faint plumbeous band overlaid with silvery. This species 
very much resembles JSf. atlierinoides caddoensis Meek, of the Ozark region, but the speci- 
mens at hand are too small for positive comparison. 
8. Hybopsis gelidus (Girard). Abundant; the longest specimens measure 3 inches in length. Body 
elongate, robust, not much compressed; dorsal region in front of dorsal fin compressed to 
an edge; profile curved (convex) from snout to dorsal fin; snout bluntish, overhanging the 
large horizontal mouth; barbels at posterior end of maxillary, long; eye small, high up, its 
diameter 5 in head; caudal peduncle slender. Caudal fin deeply forked, the middle rays 
less than half the length of the longest rays, the lower lobe dusky. Dorsal fin with first 
ray rudimentary and less than half the height of the fin ; the second ray produced into a 
filament, which is from one-third to one- fourth as long as the entire ray. Dorsal rays, 8; 
anal rays, 8. Head, 4£ in length; depth, 5£ to 5£; scales 45, about 18 scales before the 
dorsal fin. The scales are smaller in this region than on the rest of the body. Teeth, 
1, 4-4, 1, hooked and crenate. Lateral line complete ; color, light olivaceous with a very 
faint plumbeous band on sides, overlaid by silvery, silvery luster very faint. 
9. Platygobio gracilis (Richardson). Flat-lieaded chub. Common; length, 3f inches; scales, 50 to 
54 ; teeth, 2, 4-4, 2, without grinding surface, hooked at the tips, the first tooth rather more 
slender than the others; eye, 4 in the head; head, 4f ; depth, 5£; barbel well developed; 
color, light olivaceous, silvery, no markings at all. 
10. Dorosoma cepedianum (Le Sueur). Gizzard shad; Hickory shad] Mud shad. Rare. 
11. Hiodon alosoides (Rafinesque). Moon-eye; Toothed herring. Rare. 
