26 
Cope. | 562 (Jan, 18, 
bone. The latter is about as long on its superior sutures as it is deep at 
the orbit. It presents a distinct preorbital angle above a prominent tuber- 
cle, The occipito-pariétal suture extends well forwards, 30mm. in advance 
of the crest. The squamosal does not reach to the lateral occipital crest. 
The infraorbital foramen occupies the position it has in the A. ryderanus. 
In a young specimen of A. guyotianus it has the same position as in 
the adult. The frontal foramina are about as far apart as each is from the 
supraorbital border. There is a postpariétal foramen on the pariéto squa- 
mosal suture, and there are three postsquamosals, two of them near 
together, and near the posterior suture, the other below the postpariétal 
foramen. Horamen ovale oval, about as large as the / rotundum, and 
separated from the foramen lacerum by the produced base of the inferior ala 
of the sphenoid bone. Palatine foramen opposite the third deciduous pre- 
molar. 
Superior canine teeth robust, bases of crown one-half lenticular, the pos- 
terior face truncate. A considerable diastema anterior to first premolar, and 
a short one behind it. Other teeth in continuous series. First and second 
premolars two-rooted ; absolutely simple. Third and fourth crown of first 
of usual form, First true molar smaller than second. Enamel minutely 
roughened, 
Measurements. M. 
Length from supraoccipital crest to canine inclusive... .180 
és ie fs Ce CR OULO Sie MULLEN ee ee OOO 
i al My « —““ nenultimate molar. .108 
“ hy ey OTD: COTA): y aOD 
" Mi " oe TOO ny Om ONG 9 126 
ue Of BURIAL CVORT cui wermeens onee TN ele ORS: 
" “superior molars (last included)......... ee, WOO 
ihe nl VEGMIOIBIE ys vhheed's rad Velvet san VOU 
Hiatioters Nod § anteroposterior,........ A Wa eee Na Wave CO Oe 
COMMEVOLRO IN sels v ns udee nya l evirr ey ULM 
WONVELOPORTCTION ites veers obey views 1 OLGO 
Diameters M. ii 
C PUMEVCTRG Vane REN Flies Levee Uru een OeU 
Width of skull at postglenoid inclusive ..........06.+. .O77 
iy ‘middle of ZyG@Omas.. 2... ys. Cann t ey 050 
nf ba ‘fundus of canine alveolus..:........ .088 
ie between canines........... Ke ULPOV Vee buN eee iO 
si Aas BOCOMG THUS TOUTS 5 view y eben Ve ud tenis . 088 
OF SKULL At DOBTITORTA] PVOCEBSOBS sc devveisieveen) sO0G 
Mii My “* between anterior rims of orbits........ .066 
The label from this specimen is lost. It is, however, from Oregon, and 
to judge from the color, from the true John Day epoch, rather than the 
North Fork bed. 
