Tl2LEOST8 FllOM KlSSliLL SUBSTAGE. 27 



distance from tip of muzzle to occiput; maxillaries appar- 

 ently toothless; premaxillaries armed with very small conical 

 teeth; orbits large; vertebne about 3() in number; dorsal fin 

 having a long })asis, consisting of an anterior triangular, 

 more elevated, closely rayed lobe, which is at least for the most 

 part soft-rayed, having not more than three or four of the 

 anterior rays simple and regardable as slender spines, and of 

 a posterior less elevated lobe in which the rays are few, 

 widely interspaced, and much shorter and slenderer than 

 those of the anterior lobe, the anterior and posterior lobes 

 being connected by a portion in which the rays are obsoles- 

 centj pectoral fins subinferior, consisting of numerous small 

 rays; pelvic fins abdominal, placed posterior to the front lobe 

 of the dorsal; anal fin with short basis, its rays articulated 

 and distally dissected, except the first, which is simple; 

 caudal fin deeply forked; scales cycloid; lateral line extend- 

 ing along the middle of the sides. 



Syll^mus latifrons Cope. 

 Plate I, figs. 1-6. 



Syllcpmus latifrons Cope. Report (Hayden) U. S. Geological Sur- 

 vey of the Territories, Vol. II. pp. 181 and 273; 1875. Report (Wheeler) 

 U. S. Geographical Surveys West of the One Hundredth Meridian, Vol. 

 IV, Pt. II, p. 27, Plate XXIII, tigs. 1, la; 1877. Stewart, University 

 Geological Survey of Kansas, Vol. VI, p. 384, Plate LXXII, fig. 2; 1900. 



Body relatively stout in the anterior and middle region, 

 broadest a little in advance of the middle. The rostrum, 

 viewed from above, has the form of an elevated, apically 

 truncated isosceles triangle. As to length of basis, the dorsal 

 fin equals at least nearly a fourth of the total length of the 

 fish, and has the posterior rayed lobe about ec^ual to the an- 

 terior, the subrayle.ss interval being somewhat less extended 

 than either lobe. There are about 13 or 14 rays in the an- 

 terior and at least 7 in the posterior lobe, those of the latter 

 lobe being placed (in the Lincoln county specimen) at inter- 

 vals of about 5 mm. All but the anterior three or four of 

 the rays of the anterior lobe are distally tlissected, and all 

 except the rudimentary first are cleft at base, each embracing 



