of Selborne 179 



fruit; so that these birds apparently subsist on insects 

 and fruits : nor was there the least appearance of bones, 

 feathers, or fur to support the idle notion of their being 

 birds of prey. 



The sienium in this bird seemed to us to be remark- 

 ably short, between which and the ayius lay the crop, 

 or craw, and immediately behind that the bowels against 

 the backbone. 



It must be allowed, as this anatomist observes, that 

 the crop placed just upon the bowels must, especially 

 when full, be in a very uneasy situation during the busi- 

 ness of incubation ; yet the test will be to examine 

 whether birds that are actually known to sit for certain 

 are not formed in a similar manner. This inquiry I pro- 

 posed to myself to make with a fern-owl, or goat-sucker, 

 as soon as opportunity offered : because, if their information 

 proves the same, the reason for incapacity in the cuckoo 

 will be allowed to have been taken up somewhat hastily. 



Not long after a fern-owl was procured, which, from 

 its habit and shape, we suspected might resemble the 

 cuckoo in its internal construction. Nor were our 

 suspicions ill-grounded; for, upon the dissection, the 

 crop, or craw, also lay behind the stei-niim^ inunediately 

 on the viscera, between them and the skin of the belly. 

 It was bulky, and stuffed hard with \^xgQ pha/cEnrr, moths 

 of several sorts, and their eggs, which no doubt had been 

 forced out of those insects by the action of swallowing. 



Now as it appears that this bird, which is so well 

 known to practise incubation, is formed in a similar 

 manner with cuckoos. Monsieur Herissant's conjecture, 

 that cuckoos are incapable of incubation from the 

 disposition of their intestines, seems to fall to the 

 ground : and we are still at a loss for the cause of that 

 strange and singular peculiarity in the instance of the 

 cuculus canonis. 



We found the case to be the same with the ring-tail 

 hawk, in respect to formation ; and, as far as 1 can 

 recollect, with the swift ; and probably it is so with many 

 more sorts of birds that are not granivorous. 



I am, etc. 



