1004 The American Naturalist. [December, 
sively of other subregions is small, while a larger number are 
restricted to parts of it. Verrill divided it into four districts, 
viz.: the Carolinian, the Alleghenian, the Canadian, and the 
Hudsonian. These are distinguished by the ranges of mam- 
mals and reptiles, and the breeding-places of birds. The Caro- 
linian fauna extends in a belt north of the Austroriparian 
subregion, from Long Island, south of the hill region of New 
Jersey, to the southeastern corner of Pennsylvania, and thence 
inland. It embraces a wide belt in Maryland and Virginia, 
and all of central North Carolina, and then narrows very 
much in passing round south of the Alleghenies of Georgia. 
It extends north again, occupying East Tennessee, West Vir- 
ginia, Kentucky, Indiana, the greater parts of Illinois and Ohio, 
and the southern border of Michigan. It includes southern 
Wisconsin and Minnesota, all of Iowa, and the greater part of 
Missouri. The Alleghenian embraces the States north of the 
line just described, excepting the regions pertaining to the 
Canadian fauna, which I now describe. This includes north- 
ern Maine, New Hampshire and Vermont, with the Green 
Mountains, the Adirondacks and summits of the Allegheny 
Montains as far as Georgia. It includes Canada east and north 
of the lakes. The Hudsonian fauna is entirely north of the 
isothermal of 50°. It has great extent west of Hudson’s Bay, 
and is narrowed southeastward to Newfoundland. 
The information as to the distribution of the Batrachia and 
Reptilia now at hand, points to the following conclusions. The 
Hudsonian fauna need not be further referred to here, as it is 
part of the Holarctic region. The Canadian is sustained, as 
defined by the range of certain Batrachia. The demarkation 
between the Alleghenian and Carolinian is determined by the 
northern limit of most of the species common to the Eastern 
and Austroriparian subregions. An important division is indi- 
_cated by the boundaries set to the range of certain species by 
“the Allegheny Mountains. This division affects chiefly the 
Carolinian district of Verrill, and I therefore propose to abolish 
that name, and replace it by the two terms Cisalleghenian for 
Eastern, and Transalleganian for the Western districts. They 
are separated from each other by the Alleghenian district of 
