ITS FOOD 175 



nest and topples it over ; nor does it rest until 

 it is the sole inhabitant of the structure. This 

 action of the young cuckoo seems to have been 

 first recorded by the famous Dr. Jenner, who, 

 according to Yarrell, was asked to investigate 

 the subject by John Hunter, and published the 

 result in the Transactions of the Royal Society 

 for 1788. 



The food of the cuckoo consists of insects of 

 all sorts, and largely of caterpillars, grubs and 

 the like. It seems to be especially fond of 

 the hairy caterpillars sometimes called ' woolly 

 bears,' the gizzard having been found covered 

 with these hairs adhering to it by their points. 

 It must, therefore, be considered to be a useful 

 species, although it doubtless causes many 

 broods of our little birds to come to naught. 



It is a puzzling and probably an unanswerable 

 question as to the ' reason why ' of this strange 

 habit of the cuckoo. It is known to lay its 

 eggs only at an interval of several days, and 

 some hold that this may explain the necessity 

 of the parasitical habit, as it would be a matter 

 of weeks before all the clutch were laid and 

 ready for incubation ; but this is also the case 

 with some of the owls, where one finds a half- 

 fledged nestling, an egg ready to hatch and one 

 new laid all in the same nest, and yet they have 



