31. CYPEINID^ HYBOGNATIIUS. 
157 
less than one-third the length of the head and a little less than the in- 
terorbital width. Ventral lin nearly reacliing vent. Color dnsk^’, with 
a black lateral band. Fins plain. Head 5 in length, with caudal ; 
depth the same. D. 8; A. 8; scales 5-34-3. L. 24 inches. Medina 
Kiver, Texas. {Cope, MSS.) 
aa. Suborbital bouea short and deep. 
1§0. 13. piacitais Grd. 
Head short and bhintish. Body stoutish. Eye small, .shorter than 
snout, about 5 in head. Scales moderate, abont 1C in front of the dor- 
sal. Size comparatively small. Grayish above, silvery below. Head 
4;|; depth 4.^. H. 8; A. 7; Lat. 1. 40; teeth 4-4. Mississippi Valley to 
Utah. (I’ossibly two species are here included.) 
(Girard, Proc. Acad. Nat. Sci. Phila. 18.^6, 18‘2: Hi/bor;natlius ^mchalis Cope, Proc. 
Amer. Phil. Soc. Phila. 1874, 6(5: HyboynatUus nttckalis Jordan, 289; i)robably not of 
Agassiz.) 
ciaa. Suborbital bones unknown ; small species of the Texan region. 
ISl. II. CB>isco|>iis (Grd.) Jordan. 
Slender and graceful, fusiform in profile, and compressed, with the 
back slightly arched. The head is large, forming abont the fifth of the 
length. Eye large and subcircular, the diameter 3.J in head. Fins 
moderate. Scales large, the lateral line following the middle of the 
flanks. Husky abov'e, a blackish band along the sides, ending in a 
dusty blotch at base of caudal. Fins unmarked. Scales with fine 
black dots. D. 8; A. 8; Lat. 1. 39. L. 3 inches. Eivers of Texas. 
{Girard.) This or some very similar species occurs in Southern Illinois. 
{Forbes.) 
{Dioiula episcopa, serena, texensis, papuUs, argeniosa, and vhrysitis Girard, Proc. Acad. 
Nat. Sci. Phila. 1856, 177-178.) 
18§. II. flitviaSilis (Grd.) Jor. 
Form, size, and coloration of H. amarus, but the month and eye 
smaller and the scales smaller. I). 8; A. 7; Lat. 1. 40; 40 scales before 
dorsal. Snout tnbercnlate in spring males. Fie tv Leon. {Girard.) 
{Algoma jliiviaiiUs Grd. Proc Acad. Nat Sci. Phila. 1856, 181.) 
** Body short, deep, compressed, the depth about two-sevenths of the length. 
189. BI. melaiiops (Grd.) Jor. 
Head moderate, 4-^ in length. Snout rounded. E^’e medium. Black- 
ish above; sides smoky, with black dots; a black spot at base of caudal. 
Depth 34. D. 8; A. 7; Lat. 1.43; teeth 4-4. L. 2.^ inches, llio Grande 
region. {Girard.) 
{Dionda mdanops and couclii Grd. Proc. Acad. Nat. Sci. Phila. 1856, 178; Jordan, 
Bull. U. S. Geol. Surv. iv, No. 2, 402.) 
