NATURAL HISTORY OF SELBORNE. 203 



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 sternum, imme- 

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

 was bulky, and stuffed hard with large phalanx, 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 prac- 

 tise 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 cucuhts canonist 



We found the case to be the same with the ring-tail hawk, in 

 respect to formation ; and, as far as I can recollect, with the swift ; 

 and probably it is so with many more sorts of birds that are not 

 granivorous. 



I am, &c. 



* There is nothing in the anatomical structure of the cuckoo to prevent its performing 

 all the duties of incubation ; parasitism is extended over a considerable number cf species, 

 and probably exists among most of the Cuculidce ; a large black species, Eudyttantys 

 orientalis, has had its habits detailed by Mr. Blyth, in "Contributions to Ornithology for 

 1850." It selects a species of crow generally for the foster-mother, and it is a remarkable 

 instance of design that the eggs of both birds are nearly similar in cobur, that of the 

 cuckoo being rather smaller in size. It is suspected that this species breaks the eggs of 

 the crow before depositing its own, and there seems little cause to doubt that it lays 

 several eggs at the usual periods, the same as other birds. The genus Dolyconyx^ among 

 the Icterine birds, also breeds parasitically, while several species of birds depute the 

 office of incubation to artificial heat, of which the most remarkable is the hotbed-making 

 Megapodius of Australia. There is another form which this habit assumes, common- 

 ality of hatching, as in Crotopkaga, where various individuals make use of a common nest 

 and hatch by turns. The whole subject is very curious, but there is a difficulty in pro- 

 curing exact details of the habits of foreign species. 



