THE RODENTS. 257 
the long-tailed Lemur, the short-tailed Lichanotus, and 
the Stenops, the latter of which seems to be very closely 
allied to the probable ancestors of man among the Semi- 
apes. The short-footed as well as the long-footed Prosimize 
live widely distributed over the islands of southern Asia 
and Africa, more especially in Madagascar; some live also 
on the continent of Africa. No Semi-ape, either living or 
in a fossil state, has as yet been found in America. They 
all lead a solitary, nocturnal kind of life, and climb about 
on trees. (Compare vol. i. p. 361.) 
Among the six remaining orders of Deciduata, all of which 
are probably derived from long since extinct Semi-apes, the 
order of Gnawing animals (Rodentia), which is rich in 
forms, has remained at the lowest stage. Among these the 
squirrel-like animals (Sciuromorpha) stand nearest akin to 
the Pedimanous Marsupials. Out of this primary group 
the mouse-like animals (Myomorpha) and the porcupine- 
like animals (Hystricomorpha) developed probably as two 
diverging branches, the former of which are directly connected 
with the squirrel-like animals, by the eocene Myoxida, the 
latter by the eocene Psammoryctida. The fourth sub-order, 
the hare-like animals (Lagomorpha), probably developed 
only at a later period out of one of the other three sub-orders. 
Very closely allied to the Rodentia is the remarkable 
order of Pseudo-hoofed animals (Chelophora). Of these there 
now live but two genera, indigenous to Asia and Africa, 
namely, Elephants (Elephas), and Rock Conies (Hyrax). 
Both have hitherto generally been classed among real 
Hoofed animals, or Ungulata, with which they agree in the 
formation of the feet. But an identical transformation of 
nails or claws into hoofs occurs also in genuine Rodentia 
29 
