White and Cope—The Green River Group. 445 
vertebrae, three times; and the depth of the body at the ventral 
fins enters the same two and two-thirds times. The muzzle is 
short and obtuse, and the mouth opens obliquely upward. 
The orbit is very large, and entgrs the length of the head to the 
border of the operculum three times, and is one-third of itself 
longer than the muzzle. 
The radial formula is: D. IX—12; C+17+; A.V—14; V.?; 
P. 18. All the soft rays are fissured distally. The dorsal spines 
merease in length to the last one, as do also the anals. The 
pectoral rays reach to below the sixth dorsal spine, and beyond 
the extremity of the ventral fin, which does not quite reach the 
anal. The soft rays of the anal extend to a point below the 
extremity of the vertebral column, forming a well-developed 
n. The extremity of the soft dorsal is lost. The external 
rays of the caudal fin are a little longer than the median. The 
Spine of the ventral fin is not strong. The caudal pedunele is 
moderately narrow. The vertebral column is convex upwar 
anteriorly : no., caudal XVI; abdominal XII to the edge of the 
operculum. A caudal vertebra preserved in place has two lat- 
eral fossee separated by a horizontal keel. The abdominal cav- 
ity extends posterior to the anterior spinous rays of the anal 
in, so that the anterior interhemals are directed upward and 
backward. The ribs are long. There are four interneural 
bones anterior to the dorsal fin. The postcoracoid is elongate. 
There are seven or eight longitudinal rows of scales visible 
above the vertebral column, and sixteen below it; the size 
diminishing rapidly downward. All the bones of the head 
excepting the muzzle and jaws are covered with scales. There 
are six rows on the cheek below the eye. The scales of the 
body have the basal radial grooves and ridges few and coarse. 
The external surface is finely but strongly rugose with tuber- 
cles or grains, with a trace of fine concentric lines across the 
superior and inferior edges. Marginal denticles small. The 
interior faces of the scales which cover part of the fossil dis- 
play numerous very close and fine concentric lines, with a 
small triangular rough area extending from the edge toward 
the center. 
Measurements : 
Total length, with caudal fin ...-.....---+-------+-+<.= .116" 
PigGh ot Croat of dovaal Oy cos ens ee wenn ee 033 
Wength of caudal fin to base of vertebra..--... -------- °0247 
weneth of caudal vertebra... ... .-..-----+4- ---+ 6+7-.-=4¢ 0365 
nL Of base OF AGIOAL FM ooo won na on cee ke eee oe 0325 
amneth of base of sult Goraal-...- .. .. .-------- ---~++4- 015 
Length of seventh dorsal spine -----..---------------- 017 
sength of third dorsal ray = -------.<-------.--------- 020 
