ee ee 
‘ 
! 
me 
1871.] 2 3 [Cope. 
proaches the basis of the last tooth ; (reaches the tooth line at the fifth in 
HT. corypheus.) 
The occipital crest is low and directed obliquely forwards from the for- 
amen magnum. The suspensoria are stout, and directed at an angle of 
45° in both the superior ard posterior directions. The basisphenotd is 
strongly keeled below. The guadratum is like that of H. corypheus in 
its massive external angle and ridge, but differs in the shorter hook and 
the non-interruption of the groove between the external angular ridge 
and the knob below the meatus. The cervical and dorsal vertebra display 
the same disproportion in size, observed in H. corypheus. 
M. 
Jieniothe os quatinailnins cs oie tiv. sen ieee comes 35k Tm ue 0.081 
Wadth. artioulam extremity Of -d0s 0 2 joe KR i oe eee 038 
dsenpth Cemtany DONG nia Wits veaginene ssid due Se Sehr sis Sores 4 28 
oy toot ol do, = third: from bebitid<:......<..<2. 4... .022 
“ CLOW I OBIS «ii seta wah ses cl CM hee siete 1 sae .016 
‘& suspensorium from foramen ovale............+--:: .108 
otaldength cranium QS Ui en viee, oiias sien en 58 
HoLcoDUs MUDGEI, Cope. 
81. Hayden’s 
oUt 
Liodon mudgei, Cope, Proc. Am, Philos. Soc., 1870, 
Survey Wyoming, etc., 1871, p. 581. 
The specimen of this species obtained by Professor Mudge on the 
Smoky Hill River, is the only one known to the writer. The characters 
distinguishing it are the following : 
Vertebre without rudimental zygosphen. Quadrate bone with plane 
surfaces from the proximal articular surface and the external obtuse angled 
ridge to the meatal pit ; the latter therefore not sunk in a depression as 
the other species. 
The frontal bone is like that of H. ictericus, furnished with an open 
olfactory groove on the inferior face ; it is wider over the orbits. 
A re-examination of the vertebre of the type specimen, which J de- 
seribed as having compressed centra, renders it probable that they have 
been so modified by pressure as to render their normal shape a matter of 
uncertainty. 
LIODON, Owen, Cope, emend. 
Trans. Am. Philos. Soc., 1870, p. 200. 
Vertebre withont zygosphen and zygantrum. Palatine bones separated 
from each other, narrowed, the teeth more or less pleurodont. Chevron 
bones articulated freely with the caudal vertebra. 
This genus embraces several species from the Kansas Chalk, which 
range in size from the most usual in the last genus, to the largest known 
in the order. 
LIODON CURTIROSTRIS, Cope, sp. nov. 
Characters. Cervical and dorsal vertebr with transversely oval artic- 
ular faces, which are little depressed, and though not continued to the 
A. P. S—VOL, XII—2I. 
