FOSSIL MAMMALS OF THE ORDER DINOCERATA. 151 
meet the frontals. 11th, The lateral and posterior cranial crests. 
12th, The very small molar teeth, and their vertical replacement. 
13th, The small lower jaw. 14th, The articulation of the astrag- 
alus with both the navicular and cuboid bones. 15th, The absence 
of a hallux. 16th, The absence of a true proboscis. The last 
character may be fairly inferred from the short anterior limbs, the 
moderately lengthened neck, and the very elongated head, which 
rendered -a proboscis unnecessary, as the muzzle could readily 
reach the ground. The small nasal opening —smaller even than 
that of the rhinoceros or tapir—also testifies against it, while the 
nasal horns, and the sharp decurved canines would seriously have 
interfered with such an organ, had it been present. 
The horns of the Dinocerata were a remarkable feature. Those 
on the nasal bones were probably short; dermal weapons, some- 
thing like those of the rhinoceros, but much smaller. Those on 
the maxillaries were conical, much elongated, and undoubtedly 
formed most powerful means of defence. The posterior horns 
were the largest, and their flattened cores indicate that they were 
expanded, and perhaps branched. All the horn-cores are solid, 
nearly smooth externally, and none of them show any indication 
of a burr. Whether both sexes had horns, cannot at present be 
decided, but this was probably the case. 
The remains on which this description is based were found in 
the Eocene deposits of Wyoming, and are now in the Museum of _ 
Yale College. A more complete description, with full ae ae 
tions, is in course of preparation. 
In addition to the descriptions mentioned above, Prof. Cope has — 
since proposed the generic name Eobasileus,* and indicated three — 
species, which apparently are not distinct from those previously 
described by Dr. Leidy and the writer. One of the species named - 
by Prof. Cope (Hobasileus furcatus) is based on what he regards , 
as cade of the nasal bones. The — borari indi 
ie 
hase from Wyoming bear various dates ee 
from July 11th to October 12t a 
October 29th, and some of pees certainly not until ‘about amonth later. As now pub- 
BURIOECr 
antedated. as the 
+h ee Caen 5 ane S 
