64 THli CUCKOO. [cHAPTm. 



each other. Many theories, even phrenological theories, 

 have been advanced to explain the origin of the cuckoo 

 laying its eggs in other birds' nests. M. Provost alone, I 

 think, has thrown light by his observations * on this puzzle : 

 he finds that the female cuckoo, which, according to most 

 observers, lays at least from four to six eggs, must pair 

 with the male each time after laying only one or two eggs. 

 Now, if the cuckoo was obliged to sit on her own eggs, she 

 would either have to sit on all together, and therefore leave 

 those first laid so long, that they probably would become 

 addled ; or she would have to hatch separately each egg or 

 two eggs, as soon as laid : but as the cuckoo stays a shorter 

 time in this country than any other migratory bird, she 

 certainly would not have time enough for the successive 

 hatchings. Hence we can perceive in the fact of the cuckoo 

 pairing several times, and laying her eggs at intervals, the 

 cause of her depositing her eggs in other birds' nests, and 

 leaving them to the care of foster-parents. I am strongly 

 inclined to believe that this view is correct, from having 

 been independently led (as we shall hereafter see) to an 

 analogous conclusion with regard to the South American 

 ostrich, the females of which are parasitical, if I may so 

 express it, on each other ; each female laying several eggs 

 in the nests of several other females, and the male ostrich 

 undertaking all the cares of incubation, like the strange 

 foster-parents with the cuckoo. 



I will mention only two other birds, which are very 

 common, and render themselves prominent from their 

 habits. The Saurophagus sulphuratus is typical ot the 

 great American tribe of tyrant-flycatchers. In its structure 

 it closely approaches the true shrikes, but in its habits may 

 be compared to many birds. I have frequently observed 

 it, hunting a field, hovering over one spot like a hawk, 

 and then proceeding on to another. When seen thus 

 suspended in the air, it might very readily at a short 

 distance be mistaken for one of the Rapacious order ; its 

 stoop, however, is very inferior in force and rapidity to 

 that of a hawk. At other times the Saurophagus haunts 

 the neighbourhood of water, and there, like a kingfisher, 

 remaining stationary, it catches any small fish which may 

 come near the margin. These birds are not unfrequently 

 kept either in cages or in courtyards, with their wings cut. 

 They soon become tame, and are very amusing from their 



* Read before the Academy of Sciences in Paris. " L'Institut," 1834, p. 418. 



