SHUFELDT. | OSTEOLOGY OF THE TETRAONIDA. 657 
several seasons had the opportunity to study these birds in the very 
heart of their native haunts; observed them under all manner of cir- 
cumstances, both young and old; but the bird and its habits are so well 
known at the present writing that personal experiences will be almost 
superfluous here. 
For the species and varieties of Bonasa, we find that the type, B. wm- 
bella, is found throughout the eastern districts, it being the Partridge of 
New England and the Pheasant of the South. This form intergrades 
with the first variety that we find as we proceed westward; that is, B. 
umbella umbelloides, a geographical race found in the Rocky Mountains 
and British America. The last variety, B. umbella sabinii, the Oregon 
Grouse, is the Pacific coast form. The best authorities allow that the 
varieties of the type of this Grouse owe their differences in coloration to 
geographical modifications. 
The extent of this intergradation is well described in the History of 
North American Birds, already cited. After presenting a synopsis of 
the varieties, it reads as follows: 
The above synopsis is intended to present in the simplest form the characteristic feat- 
ures of the three definite races of this exceedingly variable species, as exhibited in 
a light-rusty rufous-tailed form of the Atlantic States, a pale, gray, ashy-tailed form 
of the Rocky Mount- 
ains of the United 
States and British 
America, and a dark- 
rusty rufous- tailed 
form of the Northwest 
coast region. These 
three, when based on 
specimens from the re- 
gions where their char- 
acters are most exag- 
gerated and uniform, 
appear sufficiently 
distinct ; but when we 
find that specimens 
from the New England 
States have the rufous 
bodies of umbellus, 
and gray tails of wm- 
beltoides, and continue 
to see that the transi- 
tion between any two 
of the three forms is 
gradual with the local- 
ity, we are unavoid- f 
ably led to the conclu- Bonasa ambella. 
sion that they are merely geographical modifications of one species. 
Pediecetes presents us with two forms, already given in our enumera- 
tion of species and varieties ; the first, P. phasianellus is found pretty 
generally throughout British America and to the northward of our 
boundary. It also occurs in Alaska. P. phasianellus columbianus sup- 
plants this species, being a variety of it, and is found in the prairie re- 
gions west of the Mississippi River, and has even been taken as far east 
as Chicago. 
In Wyoming, I found them during the spring and winter months in 
large numbers along the banks of the Platte River and the streams 
and creeks that empty into it. During the summer months, however, 
they desert these localities and resort to the hills and mountains, where 
many of them breed. 
As in the genus just alluded to, Cupidonia has its type and a variety. 
42 H 
