182 



or possibly Jurassic beds at the base of this granitic mountain, and its occur- 

 rence where found was doubtless accidental. 



PELECORAPIS, Cope, gen. vov. 



This genus embraces fishes with strongly ctenoid scales and abdominal 

 ventral fins. There is a spinous dorsal fin, apparently short, and not continued 

 over the ventrals. The ribs and apophyses are slender, and the dorsal ver- 

 tebras short and pitted. The pubic bones consist of two antero-posterior 

 plates, in contact on the middle line. The anterior portion projects to a 

 median angle, and there is an angular projection of the lateral border. From 

 the angle formed by these borders, a long, cylindric rod projects forward 

 beyond the plate ; those of opposite sides slightly converging. 



The general relations of this form are to the families which combine the 

 features of the orders of physoclystous and physostomous fishes, viz, Scom- 

 bresocidm, A/herinidce, etc. The pelvis has considerable resemblance to that 

 of those families, but especially to that of Exocaetux. From this it presents 

 subordinate differences. 



Pelecorapis varius, sp. nov. 



Represented by portions of perhaps two individuals, the larger of which 

 includes a considerable part of the body, the head and tail being absent. 

 On this specimen, it is evident that the scales diminish in size toward the 

 posterior part of the body, where the}' are small ; on the anterior region, there 

 are two scales exposed, in an oblique series, in six millimeters; on the pos- 

 terior region, three and one-half and four in the same. The concealed 

 portions of the scale are sculptured with minute contiguous concentric grooves, 

 without" any radii. The exposed portion is thickened with a cementum-like 

 layer, which is marked with a few radiating lines of pores, which sometimes 

 unite into irregular grooves. Teetli of the comb numerous and strong. 

 Depth of body at pelvis, CP.074 ; length of pelvis, m .040 ; of lamina, m .022 ; 

 of rod, (T.022 ; greatest width of pelvis, m .023 ; width at basis of rods, 

 m .014; length of seventeen consecutive vertebra?, 0"'.105; diameter of a 

 dorsal vertebra, 0'".007. 



Discovered by Professor Mudge in a lead-colored clay, probably of the 

 Benton epoch, twenty feet below the hwceramus bed, two miles west of 

 Siblev, Kansas. 



