HABITS OF BIRDS 



the woodpecker, but in this case it is made to assist in the 

 capture of its food ; many other instances can, no doubt, be 

 brought forward, showing the power that birds have of ridding 

 their stomachs of that part of their food not required for their 

 nourishment. One very remarkable instance I well remember. 

 A year or two ago I found in my garden, in a small heap, about 

 a handful of the most beautiful blue pills, the size of peas, 

 and studded all over with brilliant and shining blue fragments ; 

 I Soon discovered that they were the castings of the flycatchers 

 that had a nest immediately above the spot upon which I found 

 them ; the charming colour was due to the outer skins of the 

 bluebottle flies upon which the birds had fed. All the insect- 

 feeding birds throw up pellets consisting of the refuse or in- 

 digestible parts of the insects they swallow, just in the same 

 •way as the Raptorial birds (as hawks, owls, etc.) cast up the 

 feathers, bones, hair, and food of grain-eating animals in the 

 form known as castings or pellets. 



" In conclusion, I think it may be fairly reasoned that it is 

 much more likely that the food-pellets of the male hornbill are 

 intended for the support of the female and young, and belong 

 to the natural and healthy condition of the birds whicli produce 

 them, than that they are the result of indigestion or disease. 

 For we see that the power and habit of casting up from the 

 stomach are of frequent and common occurrence among birds, 

 and we also find that the secretions of the oesophagus are 

 used as food for the young of many species of birds ; in the 

 parrots and pigeons I think this is universal. 



" Another strong argument in favour of my belief is to be 

 found in Dr. Livingstone's statement that ' the male bird, by 

 his constant attention upon the female, becomes so prostrate 

 and exhausted that a slight change in the temperature causes 

 him to fall down and die.' 



" It cannot be supposed that the mere collecting food for the 

 female is the cause of this fatality, it is doubtless the over- 

 taxing of the system by the constant secretion of this nutritive 

 matter, reminding one of the blood in the nests of the esculent 

 swifts after the birds have been robbed of the first and second 

 nests. But the most positive proof of finding this package of 

 food is given, without, however, understanding its use, in the 

 extract from the Rew T. Phillips' MS. before referred to." 



Having once established the fact, all that is required is 

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