218 THE: GENUS TINOCERAS AND ITS ALLIES. 
Cope has since called frontal bones), has at present no authority, 
the specimens described being evidently the posterior horn-cores 
of other known species. Judging from the description, the name 
E. pressicornis Cope, has no better foundation. 4th, The genus 
Dinoceras Marsh, is distinct from Uintatherium Leidy, although 
perhaps nearly related. 5th, The mammals of the above genera 
cannot be placed in the order Proboscidea, but constitute a sepa- 
rate order, Dinocerata. 6th, The presence of a proboscis does not 
directly result from the osteological characters of this group, but 
is inconsistent with them; and hence the evidence is strongly 
against it. 7th, The skull in the Dinocerata presents no distinct- 
ive Proboscidian features, and the subordinate resemblance in the 
limb-bones, I pointed out before Prof. Cope wrote anything on the 
subject. 8th, The presence of canine teeth and horns, alone, was 
not stated by me to be characteristic of a new order, but other im- 
portant characters were mentioned (p. 150). 9th, The canines of 
the Dinocerata do not correspond to the tusks of the elephant, and 
the latter are not enclosed between the premaxillary and the max- 
illary, but are inserted in the former bone. 10th, The nasal bones 
of the Dinocerata are much elongated, and do not have their free 
extremities extremely short, or deeply excavated. 11th, The fron- 
tals do not extend in front of the premaxillaries; their extremi- 
ties do not form bony projections like shovels, and they do not 
support horns or processes at both extremities. 12th, The ante- 
rior horn-cores are on the nasal bones, and not on the frontals, and 
they are not composed externally of the maxillaries. 13th, The 
middle pair of horn-cores are not on the frontals, but on the max- 
illaries, their inner inferior margin alone being formed of the na- 
sals. 14th, The tarsus and foot are not strictly Proboscidian in 
character, but show strong Perissodactyl features, e.g., in the ab- 
sence of a hallux, and in the articulation of the astragalus with 
both the navicular and cuboid bones. 
The species of Dinocerata at present known with certainty are 
the following :—Tinoceras anceps Marsh, Tinoceras grandis Marsh, 
Uintatherium robustum Leidy, Dinoceras mirabilis Marsh, and 
Dinoceras lacustris Marsh. To these should probably be added 
Megacerops Coloradensis Leidy. 
