814 FISHES——CATOSTOMIDA. 
Head very smal], short and slender, its length contained six to seven times in that o 
the body, its upper surface rounded; eye quite small, nearly median, not very high up, 
its length six to eight in that of the side of the head ; suborbital bones rather small and 
quite narrow ; fontanelle entirely obliterated by the union of the parietal bones ; mouth 
small, entirely inferior, overlapped by the projecting snout, the upper lip thick, pen- 
dent, covered with three to five rows of tubercles, the outer quite large, the inner small ; 
lower lip moderate, formed somewhat as in Catostomus, but less full, incised behind ; 
jaws without cartilaginous sheath ; muciferous system not greatly developed; opercular 
apparatus not greatly developed, the operculum smooth and narrow; isthmus moderate ; 
gill-rakers moderately long, soft; pharyngeal bones strong, the teeth stout, increasing 
in size downwards, rather wide apart; body elongate, moderately compressed, not much 
elevated, the caudal peduncle long, the greatest depth contained four to six times in 
length ; scales moderate, about equal over the body, not closely imbricated, with wide 
exposed surfaces, the number in the lateral line from 55 to 60, and about 17 in a trans- 
verse series from dorsal to ventrals; edges of scales serrate; lateral line well developed, 
nearly straight; fins rather large; dorsal fin beginning in front of ventrals and 
endiog just before anal, of about 30 rays, strongly falcate in front, the first and second 
developed rays in length more than half the length of the base of the fin, the rays 
rapidly shortened to about the eighth, the length of the remaining rays being nearly uni- 
form and all short; caudal fin large, widely forked, the lobes about equal; anal fin 
quite small, low, of 7 or eight developed rays, scaly at base; ventrals moderate, with 
ten rays; pectorals elongate, somewhat falcate; sexual peculiarities somewhat marked ; — 
the males in spring with a black pigment ; the head then covered with small tubercles; 
air-bladder with two chambers, the anterior short, the posterior elongate. But a single 
species of this singular genus is as yet known. Itis found in the waters of the Mis- 
sissippi Valley, and, although not a rare fish, it is by no means as generally abundant as 
are many others of its family. 
37. CYCLEPTUS ELONGATUS (LeSueur) Agassiz. 
Biack Hiorse; Gourd-seed Sucker; Missouri Sucker; Suckerel. 
Catostomus elongatus, LESUEUR, Journ. Acad. Nat. Sci. Phila., 1517, 103.\— RAFINESQUE, 
Ich. Oh., 1820, 60 —KirTLAND, Rept. Zool. Ohio, 1838, 16%; Boston Journ. Nat. Hist , 
v, 1845, 267.—DEKay, New York Fauna, part iv, Fishes, 1842, 203.—CUVIER et 
VALENCIENNES, Hist. Nat. des Poiss., xvii, 1844, 455.—SrorerR, Synopsis, 1846, 422. 
Cyclepius elongatus, AGASSIZ, Am. Journ. Sci. Arte, 2d series, xix, 1855, 197.—JORDAN, 
Fishes of Ind., 1875, 222; Bull. Buffalo Soc. Nat. Hist., 1876, 95 (name only); Man. 
Vert., 1&76, 298; 2d Ed., 1678; Bull. U. S. Nat. Mus., ix, 1877, 38; xii, 1878, 189.— 
NELSON, Bull. No. 1, Ills. Mus. Nat. Hist., 1876, 50.—JoRDAN and COPELAND, Check 
List, 1876, 158 (name only).—JORDAN and GILBERT, in Klippart’s Rept., 1876, 53 
(name only) 
Sclerognathus elongatus, GUNTHER, Cat Fishes Brit. Mus., vii, 1868, 23. 
Cycleptus nigrescens, RAFINESQUE, Journal de Physique, 1818, 421; Ich. Oh., 1820, 61. 
Description—Body elongate, the depth four to five in length; head six to six and 
a half; eye small, six to seven in Jength of head; longest ray of dorsal a little longer 
than head ; pectorals rather longer than head; coloration very dark, the females oliva- 
ceous and coppery, the males chiefly jet black with coppery shadings ; fins dusky ; dorsal 
39; scales 9-56-7. Length, 14 to 24 feet; weight, 2 to 15 pounds. 
Habitat, Mississippi Valley. 
