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BULLETIN OF THE NATURAL HISTORY SOCIETY. 
on the toes alone, but also pressed the sole of the foot to the 
ground. 
Hylopiis (as represented in the species H. Hardingi ) , clearly 
had five toes to the hind foot, but the fifth toe of the forefoot is 
mistakenly shown. In his “ Airbreathers,” Sir William Dawson 
says (p. 7): “One pair of feet [the hind feet?] appears to 
have had four claws ; the other pair may have had three or four.’’ 
So that the number of toe prints is variable in H. Hardingi, 
but it better represents the type of the genus than H. Logani. 
Sir William’s description of H. Hardingi is as follows (“Air- 
breathers,” p. 8) : “ Dr. Harding found on one of these slabs a 
very distinct series of footprints, each with four toes and a trace 
of the fifth.” 
As the stride in H. Hardingi was five and a half inches, the 
track was probably that of an animal more than twice this length, 
i. e., more than a foot long. The width of the track was two and 
a half inches. 
In this species the print of the inner pair of toes was faint, 
indeed as regards the fore foot there was not any print 
of the first digit. There were, especially as regards the fore 
foot, three master toes, which always made a strong impression ; 
in the hind foot this preponderance of the three central digits is 
not so marked, but still it is observable. The absorption, or 
weakening of the side toes, was thus in progress in these early 
forms. This process, if continued mainly in the forefoot, would 
in time give a species which would have the characters of 
Asperipes, in which the forefoot shows only three toe marks, but 
the hind retains five, and a form of footprint, not unlike that of the 
hind foot of Hylopns Hardingi. 
The tendency to this absence of the print of the outer toes 's ' 
seen in the more advanced footmarks in the typical series of 
foot])rints of H. Hardingi, where only three toe marks can be 
observed in the print of the fore foot. 
In examining the track of this animal in detail, it will be seen 
that the creature had the habit of placing the hind foot directly 
behind the fore foot in walking, so that the two prints made by 
these feet were just clear of each other. An exception is seen 
