tubercle within the crescent, which with-wearing soon becomes 
GIGANTIC MAMMALS OF THE GENUS EOBASILEUS. 157 
the frequent clumps of the Hibiscus grandiflorus, or great-flowered 
mallow, which grows along the banks of streams, the border of 
ponds, or other moist places. This plant occurs more or less 
abundantly on nearly all the prairies of Richland, Lawrence, Wa- 
bash and Edwards counties, and perhaps throughout the state 
south of latitude 38° 25’. It is one of the most conspicuous 
plants of the prairie, for when in bloom, its large, crimson-centred 
white flowers sometimes measure nearly a foot in expanse. 
THE GIGANTIC MAMMALS OF THE GENUS 
EOBASILEUS.* 
. BY PROFESSOR E. D. COPE. 
. 
A genus closely allied to the Proboscidea called Bathmodon, 
was recently (February, 1872) described by the writer as repre- 
sented by remains of the Eocene Formations of Wyoming Terri- 
tory. Investigations prosecuted during the present season, in the 
Same region, under the direction of Prof. F. V. Hayden’s Geolog- 
ical Survey of the territories, have resulted in a better acquaint- 
ance with these forms, and an approximation to a true estimate of 
their affinities. l 
The present genus, which is new and may be called Hoba- 
sileus,t is proven to be quite distinct from Bathmodon in the denti- ae 
tion of the premaxillary bone. It is narrow and edentulous and 3 
Separated from its fellow by a deep notch. The front of the max- 
illary bone supports a tusk which represents the canine. It is 
shorter than in the walrus, but longer than in the sabre toothed 
tigers, and resembles the canines of the latter in being compressed 
and sharp-edged in front and behind. A long edentulous space 
follows the canine, before the molars commence. These are of- 
relatively small size, and number 4-2. They all exhibit a single 
crescentic crest with angle inwards; but becoming straighter on- 
the anterior teeth, where they are little curved. There is a single oe 
* Read at the Dubuque Meeting of the American A iation for the Ad t 
Science. 1972. 
t Proceedings of the American Philosophical Society, 1872, p. 485 (August 20). 
