832 FISHES—CATOSTOMIDA. 
mens obtained in Illinois River by Professor A. W. Brayton; (c) a pair 
of pharyngeal bones taken by Dr. G. M. Levette from a specimen taken in 
the Wabiush at Terre Haute, where the fish is said to be abundant; (d)a 
pharyngeal bone and air-bladder from a specimen taken in Detroit River 
by Professor Baird; (¢) a pharyngeal bone from “‘ post pliocene ” depesits 
at the Falls of the Ohio by Dr. John Sloan, and (f) many specimens 
taken in fish-traps in French Broad River where it is the most abundant 
of the Suckers. Excepting Professor Cope’s original type, the above 
mentioned are the only specimens on record. 
GENUS 24. QUASSILABIA Jordan and Brayton. 
Lagochila, JORDAN and BRAYTON, Proc. Acad. Nat. Sci. Phila., 1877, 280 (preoccupied in 
conchology as Lagochilus). 
Quassilabia, (JORDAN and BRAYTON) JORDAN, Man. Vert., E. U.S, 2d Ed., 1878, 401. 
Type, Lagochila lacera, Jordan and Brayton. 
Etymology, Latin, quassus, broken or torn ; labia, lip 
Body elongated, not much compressed, not elevated; head shortish, conical, with 
lengthened snout, its length four and a half to five in body, the opercular region being 
reduced, so that the eye is well backwards; suborbital bones narrow ; fontane le large, 
widely open ; mouth large, singular in structure, inferior, the upper lip not protractile, 
greatly prolonged, its surface closely plicate; lower lip much reduced, divided into two 
distinct elongate lobes, which are weakly papillose; the split between these lobes ex- 
tends backwards to the edge of the dentary bones which are provided with a horny plate 
as in the western genus Pantosteus; the lower lip is entirely separated by a deep fissure, 
from the upper at its angle; the skin of the cheeks forms a sort of cloak over this fis- 
sure, the crease separating this skin from the lips extends dowa on the uader side of the 
head; muciferous tubes well developed ; fins moderate, of the same type asin Myxos- 
toma ; scales large, the lateral line well developed and nearly straight, with about 45 
scales in its course; air-bladder in three parts. 
But one species is known, one of the most singular of American fishes. 
AJ, QUASSILABIA LACERA Jordan and Brayton. 
Hare-lip Sucker; Splitemouth Sucker; May Sucker of the 
Scioto; Cut-lip. 
Lagochila lacera, JORDAN and BRAYTON, Proc. Acad. Nat. Sci. Phila., 1877, 280.—JoRDAN, 
Man. Vert., 2d Ed., 1878, 311. 
Quassilabia lacera, JORDAN, Man. Vert., 2d Ed., 1878, 406; Bull. U. 8. Geol. Surv. Terr., 
1878, 418; Bull. U.S. Nat. Mus., xii, 1878, 106. 
Description.—Head short, conical, with lengthened snout, the region between the eyes 
flattened and with prominent mucous ridges; cheeks and lower part of head tumid ; 
opercle very small, its greatest length scarcely greater than the diameter of the eye; 
four and one-third in length of head, two in length of snout, its situation thus quite in- 
ferior; length of top of head one and two-thirds in distance from the snout to the base 
