928 MONOGRAPHS OF NORTH AMERICAN RODENTIA. 
under the head of A. caligatus:—“There is a living animal of this species now 
in the Zoological Gardens. It was brought to England by Mr. King, Surgeon 
to Captain Back’s overland Expedition, and is figured and described in his 
recent work under the appellation of Arctomys ochanaganus. derived from the 
river upon whose banks it was caught. The Arctomys pruinosus of Pennant 
is perhaps the same with caligatus, but the brief account of it in Arctic 
Zodlogy is insufficient to determine.” This specimen, as Audubon and Bach- 
man inform us, is also the original of their Arctomys pruinosus, to which they 
likewise refer the A. caligatus of Eschscholtz. 
Middendorff, in 1851, partly from a comparison of descriptions and fig- 
ures and partly upon theoretical grounds, considered the large Marmot of 
Kamtschatka as specifically identical with the A. pruinosus of Audubon and 
Bachman, both of which (including also the A. empetra of authors and the 
A. melanopus of Kuhl) he considered as identical with A. monax. Hence he 
strangely employs this name for the designation of the Kamtschatkan species, 
previously named A. camtschatica by Brandt. At the same time, he was 
inclined to regard the A. caligatus, owing mainly to differences of color, as dis- 
tinct from the Kamtschatkan Marmot and from the A. monaz of North America. 
Dr. Richardson, apparently on the authority of Harmon and the fur 
traders, gave the range of A. pruinosus as extending from latitude 46° to 62° 
in the Rocky Mountains. Pennant’s specimen is said to have come from 
Hudson’s Bay, and there are specimens in the present collection from Wash- 
ington Territory, Forts Good Hope, Liard, and Yukon, in the Mackenzie 
River District, and from Fort Henry, Alaska. Ross gives its range as extend- 
ing northward to the Arctic Circle. It hence probably ranges from the 
Columbia River northward, west of the Rocky Mountains to the Barren 
Grounds, thence eastward to Lake Athabasca, and possibly to Hudson’s Bay. 
All the specimens in the collection of the National Museum, however, from 
the region about Hudson’s Bay, belong to A. monaz. 
TABLE CXXXIX.—Measurements of three specimens of ARCTOMYS PRUINOSUS. 
+ a 
be * s o 
S H From tip of nose | Tail toend a 
2 s en. wee Length of— 3 
| 
5 A 2, 
a BS y a) 
3 a Locality. 3 & i Pay 
& | ‘3 43 & 3 $ 3 
g|38 z a PSE eS 5 
ee es os | 3 a al es Ss S 
§ 5 » | 8 EI S a Sua ae 
o fo) i} is) is] a iss] io q A 
5610 | 1059") Nortwhlandss «3.2 .: = sb oscae <eeae sae eee eee eee Rede eee 24. 00 6. 75 | 9.25 | 2.50 | 3.75 | Skin. 
5608 | 1058 }...... CE ae eas agian © ochis'p Sie nani ene eran gee <a en eet aU PRA PA Pee pert a a do. 
5603 | 1051 |...... OO wicoiec ac. -ccseueee ats au asc hema eere peer eeee 1.85 | 4.20 23.50 | 6.50 | 9.25 | 2.30 | 3.25 je- do. 
I i 
