THE ORDER DINOCERATA. 123 
the adjoining nasal, went upwards to strengthen the support of the 
horn-cores. 
The extremities were tetradactylate, and in the pes the astragalus 
articulated with the cuboid as well as with the scaphoid bone. The 
humerus was short and massive, with the great tuberosity not rising 
above the articular head, and the condylar ridge of the distal end not 
continued up the shaft. The radius, which was free, was not so 
oblique as in the Elephant. 
The femur had no pit on its head for the ligamentum teres, and 
there was not any third trochanter. The phalanges were short, as in 
the Elephant. 
The number of the vertebre are not noted by Marsh, so that I 
cannot say how many there were in the dorso-lumbar region, a point 
of great importance. There were four in the sacrum, the last being 
small and supporting a slender tail. The ribs had rudimentary 
uncinate processes. 
The name Tinoceras has been given by Marsh to a very closely 
allied species, which differs from Dinoceras in having the anterior or 
nasal horn-cores compressed on the top, larger, and projecting more 
forward; the maxillary horn-cores are also proportionately longer, 
more cylindrical, and directed slightly forward. The photographs of + 
_ this genus above referred to show very clearly that the palate was 
~ completed opposite the posterior molars by the palatine bones. The 
differences between Tinoceras and Dinoceras seem to be scarcely generic. 
Another closely allied genus, of which I have seen no description, is 
the Uintatherium of Leidy. The name Hobasileus, introduced by Pro- Page 270. 
fessor Cope, is a synonym of Tinoceras, and being of later intro- 
duction, must be sunk. 
From the facts given above, Professor Marsh is led to placing 
these undoubtedly peculiar animalia in an order different from any 
yet established, intermediate between the Proboscidia and the Perisso- 
dactylata. To me it seems much more probable that they belong to 
the Ungulata proper, and that no separate order is necessary for their 
reception. In the characters I have given, there are none which show 
them to have any true Proboscidian affinities, whilst there are several 
which seem to indicate that they belong to a family of the Artiodacty- 
lata, and not to the Perissodactylata. Among the reasons in favour 
of Dinoceras and its allies being Artiodactylate are the following :— 
The astragalus has a well-developed cuboid facet. 
. The palate is complete between the posterior molars. 
. There is no third trochanter to the femur. 
The premaxille are edentulous. 
The anterior premolar is not developed. 
gr 9 PO pt 
