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tellus. Mr. Kennicott says they are sometimes baked whole, of are bet- 
ter, parboiled in milk, and afterwards “ fatted down.” 
Regardihg the occurrence of this animal in Southern Ohio, I have the 
following note from Mr. Langdon : 
‘‘Not very common, but can not be called rare. Burrows usually found in the banks 
of small creeks, On June 11th, 1876, I noticed a Woodchuek climbing down a tree in a 
piece of woods, near Madisonville. He was about thirty feet from the ground when I 
first saw himi, and was coming down head first, although the tree was vertical or nearly 
s0, and about fifteen inches in diameter. As I was not aware that this species was in the 
habit of climbing trees, 1 made a note of the circumstance at the time. ‘The identifica- 
tion of the species was complete, as I approached within twenty feet of the animal bee 
fore it reached the gronnd, and found its burrow within a few yards of the tree: It suce 
ceeded in getting there, however, before I did, on acccunt of the dense undergrowth.” 
The above observation of this species climbing trees is, interesting. Mr. 
Kennicott states that it sometimes crawls up a leaning tree, or into thick 
clusters of bushes overgrown with vines, on which it is fond of lying in 
warm summer days. 
FAMILY CASTORIDA. 
This family has been associated with the Sciurid#, as also has Haplo- 
dontide. ‘The three families are so nearly allied as to be placed by Al- 
ston in the same serles—Sciuromorpha. 
The Beavers differ from the Squirrels in being adapted to an aquatic 
mode of life ; they also lack the strongly developed post-orbital processes 
of Scituride. Instead of truly rooted molars, with multiple fangs, short 
crowns, and tuberculated triturating surface, undergoing much change 
by attrition, as in Sciuride, the molars have, in Castoride, a long, persist- 
ent, dentinal pulp; the tecth contintie to grow for a long periov, becom- 
ing truly rooted only late in life. The teeth, moreover, are single-rooted ; 
have no well d:fined coronal portion, and change little by attrition. The 
lower jaw is massive, and its symphisial surface long. The long incisors and 
general structure of the skull indicate great incisive power—the Beavers 
being gnawers ‘‘ par excellence.” | 
The living representatives of the family belong to the genus Castor. 
Other genera are represented by fossil forms. 
Castoroides ohioensis, Foster, the ‘“‘ Fossil Beaver” of North America, as 
large as the full-grown Black Bear, exeeding even the Capabara, the 
largest of existing Rodents, has been referred to this family, but is now 
the type of the family Castoroididz,. Allen. This interesting animal was 
first described by Mr. J. W. Foster, from two mandibular rami and a radius 
ten inches long, two inches across the head, and an inch and a half across 
_ the distal extremity. 
