224 
ORIGIN OF LIFE IN AMERICA 
a number of species are now known from southern Spain and 
Portugal, owing to the researches of Mr. Thomas, Mr. Miller 
and Dr. Forsyth Major. To judge from its recent distribu¬ 
tion, these voles of the sub-genus or genus Pitymys ought 
to be of very great antiquity, yet not a single fossil specimen 
has ever been found. The most remarkable fact in the dis¬ 
tribution of Pitymys is that it is entirely confined to Europe 
in the Old World, whereas across the Atlantic, in Mexico, 
we again meet with a member of this group known as the 
Jalapa meadow vole (Pitymys quasitor). It lives there at an 
altitude of about 5,000 feet. Only two other species are 
known from North America, one (P. nemoralis) from the 
Boston Mountains in the Indian Territory, the other from 
certain areas in the eastern States. The latter (P. pine- 
torum) occurs from southern Florida to Carolina, a variety 
of it on the Allegheny Mountains, and another from Long 
Island to the borders of Illinois. The range of the three 
American species is disconnected, and confined to Mexico and 
the United States. What is the relationship of these species 
to one another, and which is the oldest, will have to be deter¬ 
mined by future researches, also whether the extinct species 
discovered in Pennsylvania by Professor Cope really belongs 
to Pitymys or Microtus proper. At any rate, there is nothing 
in the range of Pitymys that might lead us to suspect that it 
entered North America from the north-west, no member of 
the group having as yet been found in any part of Canada or 
Alaska. In Europe Pitymys is unknown in the north-west, 
whereas a number of species inhabit the south-west. Hence 
the American group of Pitymys may possibly have been de¬ 
rived from one or more species which crossed the Atlantic 
on the land connection above referred to. 
The hare family (Leporidae), as a whole, has a very wide 
distribution in Europe, Asia, Africa and America, but some 
of the sub-genera, which are gradually being raised to the 
higher dignity of genera, are confined within certain circum¬ 
scribed limits. In his study on the recent and fossil Lago- 
morpha, Dr. Forsyth Major * comes to the conclusion that this 
family might conveniently be divided, according to the osteo- 
* Major, Forsyth, “Fossil and recent Lagomorpka,” pp. 514—515. 
