VALUE OF BIRDS TO MAN. 51 
came from the insects fed to it not more than thirty-three 
minutes before it was killed. 
In summing up the results, Mr. Kirkland says: “I think, 
from what we have seen, that we might expect to find the 
gizzard empty in from one to one and one-half hours.” 
Such an experiment should be carried further, but enough 
was learned to show that the stomach of a young Crow prob- 
ably can be filled with food and emptied of the digested 
material from eight to twelve times a day during the long 
days of midsummer, when their appetites are at their best. 
Digestion in some of the smaller birds is doubtless even 
more rapid, for they are enabled to dispose of a still larger 
amount of food in proportion to their size. Mr. Owen in- 
forms us that the time required for a blueberry to traverse 
the digestive tract of his Hermit Thrush was practically an 
hour and a half. Mr. C. J. Maynard once told me that in 
a similar experiment a Cedar Bird passed the residue of food 
within thirty minutes after the food was taken. Weed and 
Dearborn found that a blackberry was digested by a young 
Cedar Bird in half an hour. 
The Number of Insects eaten by Young Birds in the Nest. 
The remarkable appetites of young birds keep their de- 
voted parents very busy supplying food most of the time 
from morning till night. The mother bird spends practically 
all her time either in searching for food, brooding, protect- 
ing, and feeding the young, or cleaning the nest (for all the 
smaller birds that nest openly are obliged to dispose of the 
excreta of their young, that it may neither befoul the nest 
nor betray its location to their enemies). Most of the visits, 
made by the old birds to the nest during the day are for the 
dual purpose of feeding the young and keeping the nest 
clean. Records kept of the number of these visits show 
the industry of the parent birds and the food capacity of 
the young. 
My assistant, Mr. F. H. Mosher, watched a pair of Red- 
eyed Vireos feeding their young on June 13, 1899. There 
were three nestlings, about one day old. At this early age 
the young of most small birds are fed mainly by regur- 
