D2 Scientific Proceedings, Royal Dublin Society. 
sinaller sized cave bear, but, of course, cannot compete with the 
huge specimens of Ursus speleeus, from German and Pyrenean 
caverns as will also appear from the table. 
A specimen of the latter selected for comparison with Irish 
crania will be observed to differ very much in relative dimensions 
of its ridges and regions. But these conditions are dependant on 
sex, age, and individual peculiarities. The following two features 
by which the skull of Ursus ferox and Ursus arctos may be dis- 
tinguished from one another were pointed out to me by Mr. Busk, 
and as far as my experience of specimens have hitherto extended 
appear to be diagnostic of these two forms, viz:—l. The jugal 
arcade is elliptical in Ursus ferox and more circular in Ursus 
arctos. 2. The posterior nasal openings are wider in the Ursus 
aretos than in Ursus ferox. 
Among fossil bears we find the Ursus fossilis or smaller Cave 
Bear agrees with Ursus ferox in both of these characters, and 
with the gigantic Cavern Bear also, only that the posterior nasal 
openings are relatively narrower in the latter than in either 
of them. In these respects the Leitrim skull is indistinguishable 
from that of Ursus ferox. It might be suggestive to consider how 
far the wider nasal openings have to do with the very acute 
sense of smell which the recent species possesses, as is well 
known to me from observing the animal in its native haunts.* 
According to Busk’s anemometer the cubic contents of the 
brain cavity in the Leitrim skull is 26 inches, but I have no 
sufficient data wherewith to compare the relative sizes in the 
extinct and recent species so as to find out whether the earlier 
race differed in any ways from recent species in the capacity of 
the interior of the cranial cavity. 
Il. URSINE REMAINS FROM LONGFORD AND WESTMEATH. 
Two crania were discovered in 1846-7 at a depth of seven feet 
from the surface in a deposit of marl beneath peat in cutting 
away a bog on the borders of the above mentioned counties. 
Both specimens are in the museum of Leeds, where they were 
deposited by the Jate Mr Denny, who formed an opinion that one 
* Wanderings of a Naturalist in India, p. 227. 
