1878. ] 513 [Cope. 
ders is gently convex downwards. The nostril is large, and is directed for- 
wards as well as outwards; the premaxillary spines are narrow. The 
form of the muzzle and jaws when in normal relation was vertical and 
compressed iu front. The premaxillary border of the jaw is rounded and 
contracted behind the nostril ; the outline then expands backwards. There 
are but two incisor teeth, of which the anterior is much larger than the 
second. Its root is irregular in section owing to the presence of one or 
more shallow longitudinal grooves. The pulp cavity of some of the larger 
teeth is much contracted opposite these grooves by the corresponding inter- 
nal face, which is disproportionately convex. The anterior two teeth of the 
maxillary bone are larger than those that follow, the anterior exceeding 
even the first incisor. The other maxillaries are smaller and sub-equal, 
excepting the last two, which are the smallest. The crowns of the teeth 
are lenticular in transverse section, the external side being much more 
convex than the internal. The cutting edges are defined from the con- 
vexity of the latter by a shallow groove at the base of each. The edge is 
not crenate as in Lelaps and allied genera, but presents much the same ap- 
pearance owing to the presence of a transverse corrugation. There are 
fourteen teeth and empty alveoli in the maxillary bone. 
Measurements. M. 
Length of premaxillary axially, to middle of maxillary 
BUMUUME 2/27 fe ro: cire- tone etareleaier svar auercvs tana <u lacevelen siecuorsecusicre' se 040 
Length of maxillary bone on alveolar edge from middle 
OL MPRA SURES: 556 cis aoestieain. oes £05 upmaeeee ot gens 230 
Greatest widih’ of ‘premaxillary .j0\,-wis's ac f< «series ois 036 
Depth of face of premaxillary bone at nostril.......... -030 
dueneth of diastema, (CHOPG))i: sais oieeieicee ae aie tee oes .032 
Depth ot maxillary at third tooth ose. eh -a)-eeacr sore -110 
ae a antepenultimate tooth........... .066 
Diameter of base of crown of first incisor tooth........ O15 
- first ma xaary: tOOths .o%5 alt syhaoiaw sie Seats OLS 
a fourth ‘< Ge. BOR OS Me ONO CSO 009 
The portion of cranium above mentioned displays a number of peculiar- 
ities. The orbit is lateral, and has a prominent and convex superciliary 
border. The zygomatic arch is so curved upwards as to complete the orbit 
behind by the intervention of a postorbital or postfrontal bone, which sepa- 
rates the malar and squamosal bones from mutual contact. In front of 
this bone a portion of the frontal forms the superciliary border, and in front 
of this, the prefrontal sends a wide process behind the lachrymal to the 
orbit. This bone resembles a nasal bone in form, and extends forwards, 
and is decurved at the extremity. The width of the descending or malar 
process of the postfrontal is such as to partially separate the orbit from the 
zygomatic fossa. The superciliary surface is swollen, and is interrupted 
by a transverse groove on the orbital part of the prefrontal. There is a 
vertical open groove on the malar process of the postfrontal. 
Several large pelvic bones corresponding with those which I have called 
PROC. AMER. PHILOS. soc. xviI. 101. 3L PRINTED MAY.17, 1878. 
