1893.] The Ancylopoda, Chalicotherium and Artionyz. 129 
posing that the ungulate carpus and tarsus of Chalicotherium 
were derived from those of Meniscotherium. 
The terminal phalanges present a greater obstacle ; is it pos- 
sible that having progressed only so far toward hoofs as to be 
called “intermediate,” they have subsequently retrogressed 
into curved claw-bearing ungues? T consider this possible but 
not in itself probable. We must not forget the manus of the 
subungulate Lemurs which bears three or four terminal nails 
and one large claw; or the phalanges. of the unguiculate 
Mesonyx which are cleft, but also flattened and very ungulate . 
in appearance. The line of division between claws, nails and 
incipient hoofs was not very sharply drawn. Another diffi- 
culty is seen in the fact that the median toe (III) of Menisco- 
therium is enlarged, it is mesaxonic; while the lateral toe (IV) 
of Chalicotherium is enlarged. 
Fig 3. Fore and hind Feet of Chalicotherium after Gervais, (from Sansan.). 
To offset these difficulties we find the striking similarities in 
the molar teeth already noted, and in the dental series as a 
whole. Meniscotherium is very exceptional in the absence of 
