208 University of California Publications in Zoology. [Vous 
until the hindermost are obtuse wedges of white contrasted 
against the sooty bistre basal portions of the feathers. The 
majority of the feathers back of the hind chest are white, but 
there are some long, flowing parti-colored (sooty and white) 
feathers in the flanks and some distinetly tawny barred feathers 
along the sides that I take to belong to the tutelar plumage. 
This bird seems to be largely in nuptial plumage, but with an 
admixture of tutelar posteriorly both dorsally and ventrally; 
in the wing coverts are a number of feathers, sooty with minute 
flecks of tawny and with obtuse white wedges at their ends. 
The wings are otherwise white. The back is largely sooty bistre, 
the feathers showing toward their ends faint and extremely 
narrow transverse and tawny vermiculation. The tail feathers 
are lacking, save for two partly grown new ones which are black, 
tipped narrowly with white. 
Another colored adult (No. 372), taken in the same locality 
and on the same date as the type, has the same sooty bistre 
ground color, but the tawny is much more extensive, more as in 
rupestris of corresponding plumage from the interior of Alaska. 
The barring of tawny is wider in pattern, so that it gives this 
bird a generally lehter coloration. The three remaining birds 
(Nos. 366-368), taken May 31, on a mountain near Hasselborg 
Lake, Admiralty Island, are adult males, still in nearly full win- 
ter plumage. But over the pileum in each case are many dark 
feathers showing through the white. These dark feathers are 
like those on the type, sooty bistre, almost dead black, flecked 
sparingly with narrow tippings or barrings of hazel. 
This new species of the variable rwpestris group I judge to 
be the Sitkan District representative. It shows the same sort 
of color characters as many other birds of the region. It is 
named for Mr. Joseph Dixon, through whose persistence and 
hardihood all of the specimens were collected. 
On the mountains around Hasselbore Lake ptarmigan were 
apparently common, but on account of the precipitousness of 
the region were very difficult to obtain. On May 30, when the 
males were yet in almost pure white plumage, females seen were 
‘ 
almost entirely gray above. ‘‘Their flight was very swift. more 
like that of a falcon than a quail. The males would fly out over 
