276 MONOGRAPHS OF NORTH AMERICAN RODENTIA. 
ward extension of two other well-marked species, namely, L. californicus 
and L. Trowbridgei, whose ranges are almost identical with that of L. 
sylvaticus var. Audubont. 
In the interior we meet with still another species (L. callotis), whose 
range extends from about the latitude of Southern Wyoming southward 
over the arid interior far into the Republic of Mexico. In the United 
States, this species also finds the Sierra Nevada Mountains a barrier to its 
westward extension, they bounding its habitat in that direction. The south- 
ern representatives of this species also constitute a seemingly well-marked 
variety (fexianus), differing mainly in possessing a stronger suffusion of 
rufous. 
In the southeastern portions of the United States, we meet with two 
species, which are confined almost exclusively to the swampy lowlands. These 
are the L. palustris, which ranges throughout the swampy districts of the 
South Atlantic and Gulf coast to Yucatan, and the Z. aquaticus, which has 
not as yet been reported as occurring to the eastward of Alabama, but which 
extends westward and southward throughout the wet lowlands of the Gulf 
coast to Yucatan and other parts of Southern Mexico. ‘These species also 
extend northward over the lowlands of the Lower Mississippi, having been 
found as far north as Southern Ohio. 
The Tres Marias Islands afford still another species (L. Graysoni sp. 
nov.)—possibly an insular form—whose nearest affines are the members of 
the L. sylvaticus section of the genus, though in some respects it is allied 
also to the Swamp-hares. 
Lepus brasiliensis is the sole representative of the Leporide thus far 
recognized as occurring in any part of South America, its range extending 
from Patagonia northward to the Central American States. It seems, how- - 
ever, to be nowhere abundant. 
The temperate portions of the North American continent, or the United 
States, thus form the region where the family reaches its maximum develop- 
ment. All the species but three (one of which, Lepus Graysoni, is prob- 
ably an insular form) are found within the territory of the United States, as are 
also, with a single exception, all of their varieties. The other two species are 
Lepus arcticus and Lepus brasiliensis—the one an arctic form, the other trop- 
ical, while the variety is the subarctic race of L. americanus. One species 
only (L. sylvaticus) is found over a large portion of the area east of the Mis- 
