GREEN, GREENISH GRAY, AND OLIVE 437 
Nevada in California. Throughout this extensive range 
the breeding season occurs some time between the first 
of May and the last week in July; and within that 
period each pair sometimes, but not usually, raises two 
broods. My own observations lead me to believe that 
in the same! zone there is, in the case of all birds, a 
difference of about five days in nesting for every degree 
of latitude. This would make the season north of San 
Francisco from three to four weeks later than in the 
San Diegan district. 
The Western Flycatcher is even less restricted in his 
selection of a building site than in choice of climate. 
On the ground among the roots of trees, up high ona 
tree branch, in the bottom of a deserted flicker’s hole, on 
a ledge of rock, he seems to follow no law but his own 
sweet will or that of his wee mate. 
The notes on this Flycatcher by Mr. Charles A. Allen, 
of Nicasio, California, seem to me well worth quoting. 
He says: “It is a very widely distributed species 
throughout this part of the State, both among the forests 
on the highest hills, where there is not a drop of water 
for long distances, and along the banks of brooks and 
streams in the lowlands; I have found its nests in all 
sorts of situations, —sometimes in a small tree, placed 
in the upright forks of the main stem; again, on the 
side of the stem where a small stub of a limb or some 
sprouts grew out; or in a cavity ina tree trunk ; against 
an old stump, or a root which had been washed down 
during a flood in the middle of a stream ; among curled- 
1 See map of life zones, p. xvi. 
