1872.] 335 
[Cope. 
rather narrow. The latter is without armature, and has some depressed 
grooves radiating towards the circumference. Length of bone vertically, 
M. .245; radius from inner curve, .09. 
The vertebre display deep lateral grooves; articular faces smooth. 
Length centrum, M. .028; diameter, .048. The fan-shaped hemal spines, 
or second of the caudal fin is like that of P. thawmas, but smaller. The 
last caudals contract in size very rapidly ; the cup of the penultimate or 
last is transverse diamond shaped. 
The fragments of the sabre-shaped spine display several layers of par- 
allel striate dense bone, and the edge is tubercularly dentate, and one 
side is much more rugose than the other. At the base, one side is flat ; 
the other convex, and there is a transversely rugose band near one edge. 
The scales are thin and cycloid, and though large are not remarkably 
so for the size of the fish. 
Measurements of Cranium. 
M. 
Length from angle of opisthotic to anterior extremity 
OLGUNIMNOIG 0 6 iii ee Cee enw ne cee Cee tey ae 0.30 
Length from same to front of prodtic................. 11 
es “ postfrontal to prefrontal across orbit..... ed. 
‘* oecipital condyle to transverse process of 
PANASPUCHO as sie ce veces seco ue tees ee ests tees Ba 
Length from do. to bottom parasphenoid emargination .055 
na parietal bone On outer stibure...... 006. 07 
Widths WO: aio OMOGen a Vaiss 6 tee es nay ee ge .014 
be do. to edge pterotic.. eA 
ss HVOMUal au MMICUIS OLOLbs: Crees ooaa tee en Cast ce 04 
ve pavasphenoid do, = ...2. 2.4 ae a ec ee .08 
jiénpth iiferior QUuadrates cs. rere. ees 20) 
. CONDYIG OF (00. isin ase ete ss te 0.08 
yu AVIMPIECHIO I Ve isn eats ween ts es 064 
The gape of the mouth of the Portheus molossus extended the whole 
length of the cranium proper, and far beyond the orbits, since the max- 
illary reaches to opposite the occipital condyle. The orbits were large. 
The lower jaw was deep, and gave the countenance that bull dog expres- 
sion from which it derives its name. The body was short or moderately 
elongate. As materials for a restoration of this fish exist, I will give 
one at a future time. 
PORTHEUS THAUMAS. Cope. 
(Saurocephalus thaumas, Cope. Proceed. Amer. Philos. Soc., 1870, No- 
vember. Hayden’s Survey, Wyoming, etc., 1871, p. 418.) 
This large species rests on a specimen without cranium, originally 
procured by Professor B. F. Mudge. The parts preserved are not distin- 
guishable from the corresponding ones in two individuals obtained by 
myself in Western Kansas, which include the greater portions of the jaws 
