418 CONTRIBUTIONS TO A REVISION OF THE 
specifically the same as the Castor fiber Linnzeus of Europe. In 1897, Dr. E. A. Mearns 
described* a subspecies of the typical Canadian animal, naming it Castor canadensis 
frondator and assigning its habitat to the “southern interior area of North America, 
ranging north from Mexico to Wyoming and Montana.” This appears to be the first 
attempt in literature to formally subdivide the American beaver, a species whose con- 
stancy of characters over the vast and varied habitat which it frequents had hitherto been 
unquestioned. There can be no doubt as to the tenability of Dr. Mearns’ “ Broad-tailed 
Beaver ” as distinguished from the Hudson bay animal, whose habitat Kuhl designated 
as “ad fretum Hudsoni” in his original description of canadensis. 
It is probable that the beavers inhabiting the Carolinas, Georgia, Alabama, Missis- 
sippi and Tennessee are equally entitled to subspecific rank. So rare has the beaver 
become in these States, however, it would probably be impossible to verify such a predic- 
tion with specimens now in our museums.*f 
From what we know of the relationships of the representatives of our eastern species 
inhabiting the Pacifie slope, we are led to expect that the beaver of that region would 
also prove separable from canadensis. A very complete series of skulls, with three adult 
and three young skins from the Cascades of Washington and Oregon, shows this to be 
the case. 
Fortunately the synonymy of the American beayer is not inyolved and requires no 
elucidation in this connection, as is shown by reference to Dr. J. A. Allen’s Monograph 
of the North American Rodentia. A synopsis of the American forms is herewith pre- 
sented. 
CaNADIAN Beaver. Castor canadensis Kuhl. 
Plate XXI; Fig. 3. Plate XXII; Fig. 3. 
Castor canadensis Kuhl, Beitr. Zool., 1820, p. 64. 
2“ Castor americanus F. Cuvier, Hist. des Mam. du Mus., 1825” (fide Brandt in Kennt. 
Sdugt. Russl., 1855, p. 64). 
Castor fiber americanus Richardson, Faun. Bor. Amer., 1, 1829, p. 105. 
Castor fiber var. canadensis J. A. Allen, Monog. N. Amer. Rod., 1877, p. 444. 
Type Locality. Hudson bay (“ad fretum Hudsoni” Kuhl). 
Geographic Distribution.—Northeastern North America, from the northern limit of 
trees south to the United States and west to the Cascade mountains ; intergrading east 
of the Mississippi river into subspecies carolinensis, south-centrally into subspecies fron- 
dator and westwardly into subspecies pacificus. 
* Proc, Nat. Mus., Vol. XX (adv. sheet, March 5, 1897). 
+ As will be seen later, such specimens have since come to hand and are described as Castor canadensis carolinensis. 
