THE CROW BLACKBIRD. 67 
Kansas was found to contain fossil remains of corals, crinoid stems, 
shells, ete. 
As previously stated, 456 nestlings are included in the 2,346 birds 
whose food has been already discussed. A separate study was made 
of these, in order to ascertain in what respect, if any, their food dif- 
fered from that of the adults. It would have given more satisfactory 
results if it had been possible to separate the younger nestlings—say 
those under 1 week of age—from the older ones, for it was noticed 
that as the young approach maturity and get ready to fly, their food 
becomes more like that of their parents. The young were collected 
from May 22 to June 30, inclusive, and represent every age, from the 
newly hatched to those about to leave the nest. The whole food, 
when separated into its two principal components, was found to be as 
follows: Animal matter, 74.4 percent; vegetable, 25.6 percent. The 
much higher percentage of animal food in the young as compared 
with the adults (30.3 percent) is at once noticeable, although it may 
be insisted that the food of the young should be compared with that 
of the adults in the corresponding season; that is, in the months of 
May and June. If this view be taken, the difference is not so great, 
The percentage of mineral matter in the stomachs is also a little 
greater than in the case of adults. 
The animal food is practically the same as that of the parent birds, 
and likewise consists chiefly of insects. These amount to 70 percent, 
43 percent more than in the adults. The animal food other than 
insects, amounting to less than 5 percent, is not important enough to 
merit attention. The insect food is made up of about the same kinds 
as are eaten by the old birds, but in somewhat different proportions. 
Adult beetles, on account of their hard shells, are not fed to very 
young birds, but a few are given to the older ones. Grubworms (the 
larvee of scarabeids) are fed freely after the first or second day. A 
little more than 19 percent of the food of the nestlings consists of 
this family of beetles, and for the most part in the form of the larve 
or grubs. Predaceous beetles (carabids) constitute about 10 percent 
of the food, weevils a little more than 3 percent, and there were 
traces of five or six other families, none of which reached 1 percent. 
Grasshoppers and crickets, the former predominating, are a favorite 
food for the young, being softer and more easily digested than beetles. 
They constitute more than 21 percent of the total food. This is nearly 
as much as the parent birds consume in August, and three times as much 
as they eat in May and June, when they are feeding the young. This 
shows that they select the grasshoppers and other soft insects for their 
offspring, while they eat beetles and other hard things themselves. 
Caterpillars constitute 6 percent of the food of the young birds, 
which is not as much as might be expected when we consider how soft 
and apparently well adapted they are for this purpose. 
