Reproduction 69 
for instance), the exact condition of their nest, to find it is 
another matter. Despite this fact and the knowledge of the 
hopelessness of such a search, I have gone over promising sites 
examining every inch for hour after hour until the sum total 
so spent had accumulated into days of time and have never 
found such a nest, i. e. with eggs just prior to incubation. Ac- 
cidentally, however, students of mine located two March nests 
with eggs that had been abandoned as the result of early April 
snows. 
It is easier, though by no means simple, to find a nest in the 
process of construction. The female at this time is assiduously 
attended by the male, and, in addition, displays a restlessness 
(runs back and forth, is quiet for short intervals only, flies up 
and away but shortly returns), quite different from any other 
period of the nesting. But she approaches the scene of her 
prospective nest with extreme reluctance while an observer is 
near, even within fifty yards, and hours of watching may be 
necessary before the nest site is located. Four recently ex- 
cavated nest cavities were found by this method and one or two 
partially constructed nests. It should be added, however, that, 
though in one case material was added after the cavity was 
found, in no case was any nest completed after its discovery. 
Hither the bird is so timid that she deserts these early starts 
upon the slightest interferences or so many starts are made (see 
below) that in no case have I been fortunate enough to find the 
one chosen for completion. Apparently Mouseley (1916), is the 
only ornithologist on record who has watched the evolution of 
a nest from the period of the excavation until the set was com- 
plete. And Mr. Wm. Chandler (Sutton, 1927) found a female 
building a nest that later had eggs, but neither of these gentle- 
men make clear just how they located the structures at their 
beginnings. 
After the bird has begun to incubate the case is far dif- 
ferent. Then, knowing that the female most frequently will 
leave her nest at from thirty to seventy-five yards, in advance of 
any intruder, in a very characteristic ‘‘casual-abandonment”’ 
flight low over the ground, one has but to march back and forth 
over the breeding territory until she is seen to leave. Frequently 
then it is necessary to reapproach the apparent nest-spot from 
different angles on subsequent visits before the nest is disclosed. 
