210 
THE MAMMALS OF MOUNT MAZAMA. 
rubricapilJa gutturalis)^ Pileolated Warbler {Myiodioctes pusillus 
pileolatus). Other species, which are common to the Canadian and 
Hndsonian Zones, will be mentioned under the latter. 
The Canadian Zone mammals which range down to the Klamath 
plain but were not found in the Hudsonian are the Weasel, Mink, 
large Skunk, Red or Pine Squirrel, and Snowshoe Rabbit. Those 
which are common to the Canadian and Hudsonian are the Oregon 
Puma, Lynx, West-coast Wild-cat, Black Bear, Western Marten, 
Columbia Black-tail Deer, Porcupine, Jumping Mouse, Long-tailed 
Vole, Gibbs' Mole, White-bellied Water Shrew, Sierra Shrew, and 
Silver-haired Bat. 
(3) The Hudsonian Zone. — The Hudsonian Zone occupies the 
summit of the mountain and descends on the south side to an alti- 
tude of about 1,850 meters (6,100 ft.) which is only a short dis- 
tance above Pole Bridge Creek. The dominant trees are Alpine 
Hemlock (Tsuga pattonii) and the Noble Fir (Abies nobilis). 
Mixed with these are numerous Alpine Firs (Abies lasiocarpa) and 
a few White-bark Pines (Pinus Albicaulis). The latter are confined 
mostly to the rim of Crater Lake and are therefore of no value in 
fixing the lower boundary of the zone. The Hudsonian belt is 
characterized by negative as well as positive elements, lacking the 
Lodgepole Pine (Pinus murrayana)^ Mountain White Pine (Pinus 
monticola) and White Fir (Abies concolor) of the Canadian Zone. 
The following Boreal species of bird breed about Crater Lake in 
the Hudsonian Zone and many of them occur also in the Canadian: 
Oregon Jsiy (Perisoreus obscurus)^ Clark's Crow or Nutcracker (ATi/ci- 
fraga columbiana)^^\'emng Grosbeak (Coccothraustes vespertinus)^ 
Cassin's Purple Finch (Carpodacus cassini)^ Crossbill (Loxia cur- 
virostra siricklandi)^ Pine Siskin (Spinus pinus), Townsend's Soli- 
taire (Myadestes townsendi), Three-toed Woodpecker (Picoides 
arcticus)^ Mountain Bluebird (Sialia arctica)^ Audubon's Warbler 
(Dendroica auduboni) and the Mountain Chickadee (Parus gambeli). 
The distinctive mammals of the Hudsonian summit of Mount 
Mazama are the Alpine Flying Squirrel (Sciuropterus alpinus)^ the 
Alpine Mole (Scapanus Alpinus), the Giant Mole or Water Rat 
