THE AMOUNT OF FOOD CONSUMED BY BIRDS. 



63 



per day, the total amount of excreta passed by each bird is 



7.5 drains. Adding the daily gain to the daily excretion gives 



8.6 drams, the daily food during the eleven days. After the 

 eleventh day more nutrition goes into feathers and less to 

 flesh, so that the gain in weight is not so great as before ; but 

 the excreta continue to 



increase in proportion to 

 the bird's development, 

 and the parents are in 

 constant attendance, so it 

 is clear that there is at 

 least no diminution in 

 the food supply after the 

 eleventh day. During the 

 fifteen days that the young 

 birds spent in the nest, 

 they devoured not less 

 than ten ounces apiece, 

 — more than ten times 

 their weight on the day of 

 flight. 



Another cedar-bird 

 taken after it had left the 

 nest, and kept under sur- 

 veillance but not confined, took a good-sized black or choke 

 cherry every ten minutes. When given two, he invariably 

 doubled the time between meals. This bird was captured 

 at night. The next morning the character of its excrement 

 indicated that there was little or no food matter in the diges- 

 tive organs. The fast was broken by two black cherries ; the 

 stones were dropped forty-five minutes later. A blackberry 

 was digested in half an hour. The cherries were given entire, 

 and their large size evidently delayed their passage from the 

 oesophagus into the proventriculus, for the bird stretched his 

 neck as if in distress after they had been swallowed awhile. 



Photographed from life. 



CEDAR-BIRD AT NEST. 



