LAND BIRDS. 241 
single tree, sometimes only a few feet above one’s head, but more often 
at heights of twelve to fifty feet. 
The nests were merely flat platforms of twigs loosely put together, small 
and scarcely hollowed, while no attempt at concealment was made. Here 
a single egg was laid and usually this was incubated and hatched alone. 
In some cases two eggs were found in a nest, and a few observers claim that 
a second egg was usually laid soon after the first one hatched, the heat of 
the young bird helping to incubate the second egg. Nevertheless most 
authorities believe that but one egg was laid by each bird, the cases in 
which two eggs were found in a nest being explained on the supposition 
that two females used the same nest. 
Much uncertainty as to the period of incubation seems to exist, different 
writers allowing from 13 to 24 days. The majority state that the period 
is 18 to 20 days, and this is the time given by Bendire (Life Histories, 
Part I, 1892, p. 188). On the other hand, David Whittaker of Milwaukee, 
who had a flock in confinement for many years, states that the period of 
incubation is “fourteen days almost to a day, and if the egg is not hatched 
then the birds desert it.” Mr. Whittaker also states that he has never 
known any of his birds to incubate more than a single egg at a time, although 
each female laid on an average three or four eggs each season, and some 
laid as many as 7 or 8 (Auk, XIII, 1896, 234-237). The eggs, scarcely separ- 
able from those of the domesticated dove, are white, unspotted, elliptical, 
and measure 1.47 by 1.02 inches. 
Studies of the large breeding places of the Pigeon show that at least in 
Michigan nesting began frequently by the middle of April and lasted 
normally until late in June or even into July; thus, the period of incubation 
being less than three weeks, and the young remaining in the nest only about 
two weeks, it seems evident that many of the birds, if not all, must have 
reared at least two broods. 
Many of the netters claim that the old birds pushed the young out of the 
nests before they were able to fly and at once deserted them leaving them 
to get what food they could from the ground for a few days, until they 
learned how to fly and were able to shift for themselves. They were said 
to be extremely fat when pushed out of the nest and this prevented them 
from starving during the interval. Meanwhile the parent birds were said 
to move away to a distance of twenty to fifty miles and at once construct 
a new nest where another squab was reared. However this may be, it 
has been repeatedly observed that for many weeks after a nesting was 
founded it continued to grow in extent, spreading more or less in all direc- 
tions, but usually becoming an elongated area, from two to four miles in 
width and often twelve to twenty miles in length, sometimes even larger. 
The nests themselves were mere platforms of twigs and small sticks, 
carelessly interwoven and so fragile as to be easily dislodged or shaken 
to pieces. In many cases the single egg was distinctly visible from below, 
through the bottom of the nest. Apparently both sexes took part in the 
construction of the nest, but in the case of birds which have been watched 
in captivity the female has been seen to arrange the material brought by 
the male. After the eggs were laid the birds took turns in brooding and the 
greatest uniformity is said to have prevailed in this respect throughout 
the entire colony. Thus several different observers agree that the males re- 
mained on the nest from nine or ten o’clock in the morning until about two 
in the afternoon when their places were taken by the females, who sat through 
the night and until about nine o’clock the next morning. The females thus 
31 
