PARKMAN’S WREN. 131 
forefeet brush the whiskers, ears, eyes, and head 
in general, I suppose, to remove particles of dirt 
accumulated in passing through the tunnel. 
It is curious to note how three species of 
eround-squirrels have replaced each other in 
accordance with the change of vegetation in our 
transit from the Dalles to where we are now en- 
camped. 
At the Dalles we saw Spermophilus Douglassii, 
the Columbia Ground Squirrel (described in 
vol. i.), extending only as far as the scrub-oak 
grew, the Fall river being its boundary going 
north towards Colville. 
Betwixt the Fall river and the Spokan, inhabi- 
ting the sandy and woodless plains, Richardson’s 
Ground Squirrel (S. Richardsonii, Cuv.) is alone 
found. After crossing the Spokan and getting 
into the timbered regions, the ground-squirrel I 
have been looking at takes its place, and extends 
from the Spokan to the slopes of the Rocky 
Mountains. , 
July 9.—To-day we have a charming drive 
through grass and open timbered land, like a 
succession of beautiful parks. Cross several 
small streams, icy cold, but clear as crystal. 
By these rivulets I noticed Parkman’s Wren 
(Troglodytes Parkmannii, Aud.). 
K 2 
