92 MEMOIRS OF THE CARNEGIE MUSEUM 
shaft) and expanded upper and lower ends. The upper half of the shaft is tri- 
hedral in cross-section, while the lower half is subcylindrical. In Archexotheriwm, 
according to Scott (87, p. 286), the upper portion of the shaft is compressed later- 
ally and has a more oval section lower down. ‘The cerato-hyal is shorter than the 
stylohyoid in about the same proportion as in Archxotheriwm. The proximal end is 
expanded and cup-shaped, and immediately below the enlarged end the shaft 
becomes quite thin transversely, but broad antero-posteriorly. The lower half of 
the shaft is still more oval in section and terminates in an enlarged end for car- 
tilaginous attachments. The bone asa whole is very like that in Archwotherium. 
MEASUREMENTS, 
Ca Gis Gel uae ate ayia NE Say A ASL Beers aise ah fe apne ee ee eats eet 883 
Distance from postorbital process of jugal to and including premaxillaries... 528 
is = iy Ca ies be cece e occipital condyle 305 
i 
Length of alveolar border of maxillary and premaxillary.............ccce0000000 465 
IDIStECS LOIN MAOMIA TE IT CISOL LO MEI s11..savscetses.ste0vcersesbaservvtinecteobeve¥ aces 330 
Greatest transverse diameter of Condyles...... .....scsescccseccessesssesccesecveeseeees 165 
Vertical diameter of condyle La monaly 
Greatest transverse diameter of skull, approximately. 
Transverse diameter of muzzle in front of orbits, approximately... 
“ce “ “e oe at P2. 
Greatest length of mandible 
Depth of mandible, inferior border of angle to and including condyle. 
sae eee a GMS tc ciees Capua clue a Rea gma metaeeeV OE avant sets VTe Ory 
‘VERTEBRAL CoLUMN. 
Atlas. — The atlas, on the whole, is very similar to that of the Oligocene genus. 
The more important differences are here given. ‘The posterior exit of the vertebrar- 
terial canal is shifted lower down on the posterior face of the transverse process 
than in Archzxotherium. In the latter genus the position of this foramen is higher 
up, or, nearly on the superior face at the base of the transverse process.» In Dino- 
hyus the facets for the axis are relatively higher and narrower, the cavities for the 
occipital condyles shallower, the neural canal narrower, and the neural spine some- 
what more prominent than in Archxotherium. The transverse process does not pro- 
ject backward nearly as much as in the Princeton specimen, and consequently gives 
to the atlas of the latter a relatively greater total antero-posterior diameter. 
Axis. —The axis of Dinohyus differs from that of Archeotheriwm in having the 
3 Tn a specimen (No. 1665) of the Carnegie Museum collection, from the Titanotherium beds, Sand Creek, Sioux 
Co., Nebraska, this foramen is placed lower down than in the Princeton specimen. 
