162 Psyche [August 
the red excrement was collected the same afternoon and dried in the 
air for two days. To facilitate the hatching of the caterpillars from 
such eggs as might be contained in the excrement, this was carefully 
broken into small pieces. Seven eggs were found but each had the 
shell slightly injured by the bird’s beak. The rest of the eggs had 
not been eaten but had been picked out of the crumbs of bread by the 
bird and thrown aside. The hatching of caterpillars from the con- 
trol eggs began on March 21 and was completed two days later, but 
the seven eggs obtained from the excrement failed to hatch, having 
dried up. 
In the following experiments the same precautions were taken, 
keeping control eggs from each cluster used and adding bits of 
cochineal so that this need not be mentioned in the case of the 
other birds. 
English Chaffinch 
A bird of this species was fed in the same way but the eggs were 
not passed in the excrement until nearly three hours after feeding. 
The excrement was dried and broken up as before but not a single 
dispar egg could be found. These missing eggs were later found 
uneaten, having been cast aside by the bird. 
English Yellow Hammer. 
A specimen of this species was fed as before but the eggs were 
placed in living larve of the meal-beetle which had been cut open 
on the last four abdominal segments to insert the Gypsy Moth eggs. 
The bird was fed with these in the morning and after an hour and 
a half they were passed in the excrement of the bird. In this case 
twelve dispar eggs were found and no sort of injury could be de- 
tected on any of them. Other eggs fed in pieces of bread were cast 
aside by the bird and not eaten. Although the caterpillars from the 
control eggs hatched normally all those fed to the bird failed to 
hatch. These changed color normally but died with a nearly 
developed caterpillar in each egg. 
Japanese Robin. 
This bird was fed on eggs placed in meal-beetle larve as was 
done with the previous bird. The bird was fed late in the morning 
and an hour and a half later the eggs were passed in its red excre- 
