PERCOMORPHI. 93 



the ventral spine is very strong^, and there are but ten or eleven soft dorsal 

 radii : here belong P. serrata, P. ci/pha, P. oxyprion, and P. testudinaria. In 

 the second, the first ventral spine is weak and slender, and there ai*e thir- 

 teen or fourteen radii of the second dorsal fin; in this division belong P. 

 Hops, P. pealei, and P. clivosa. 



A pair of superior pharyngeal bones from the Washakie basin of the 

 Bridger formation strongly resemble those of this species. 



Peiscacara serrata Cope. 



Bulletin U. S. Geol. Siirv. Terrs., 1877, p. 816. 

 Plate XIII, fig. 1. 



Form a regular wide oval, with a subequal contraction at both extremi- 

 ties. The spinous dorsal rays become longer than the soft ones, but the 

 posterior spines are shorter than the anterior soft rays, so as to produce a 

 wide emargination in the superior outline. The spines are very robust, 

 especially those of the pectoral and anal fins. The first anal spine is near 

 two-thirds the length of the second. The pectoral fin does not extend to 

 the anal, and the soft parts of the anal and dorsal, which are equal, do not 

 overlap the base of the caudal. Radii : D. X— 11 ; A. Ill— 10; C.?— 17— ?. 

 Vertebrae: D. 9; C. 14. The centra have a strong median lateral ridge, 

 which separates two fossae. 



The greatest depth is at the base of the ventral fins, or the third dorsal 

 spine; it enters the total length (with caudal fin) two and four-tenths times. 

 The length of the head enters the same three and four-tenths times. The 

 orbit is large, its diameter exceeding the muzzle and entering the length of 

 the head a little over four times. The mouth is terminal, and the premaxil- 

 lary extends obliquely downward and backward; the maxillary reaches the 

 line of the anterior border of the orbit. 



The scales are longet* than deep, and the rough surface has but a small 

 extent, and is finely granulated. The remainder of the scale is marked 

 with strong concentric grooves. Those on the gular region are small On 

 the belly, there are from twenty to twenty-five rows (about) below the ver- 

 tebral column. A row of scales extends along the postero-inferior edge of 

 the operculum. This part is well preserved in only one of my thi-ee speci- 

 mens which represent the species. 



