THE CUCKOO 478 



instincts which are so marked a characteristic of birds, and of all the 

 ln_'li- i animals. 



Ill 



After about twelve days' incubation the young cuckoo is born, 

 and sooner or later it proceeds to eject from the nest the eggs or 

 young of its foster-parent The first who appears to have noted this 

 curious fact was a French doctor, Lottinger, in a work entitled //ijrfm'/r 

 <lit coucoti (T Europe (p. 18), published in 1795. l He did no more, how- 

 ever, than record that an egg previously inside the nest (a robin's) 

 was in his absence hoisted on to its edge. He put it back, and shortly 

 afterwards saw it again on the edge. He inferred that the young 

 cuckoo, which was alone, had ejected the egg en te remnant. The 

 date of the observation was July 1782. 



It remained for Dr. Edward Jenner to witness and describe for 

 the first time the actual process of ejection. 3 On June 18, 1787, he 

 noted a hedge-sparrow's nest containing four eggs, of which one a 

 cuckoo's. Next day, June 19, the same nest contained one youn^ 

 cuckoo and one hedge-sparrow. He saw the latter ejected. 

 His own description of the incident if at follows: "With the 

 assistance of its rump and wings, the young cuckoo contrived to get 

 the bird upon its back, and making a lodgment for its burden by 

 elevating its elbows, clambered backwards with it up the side of the 

 nest till it reached the top, where, resting for a moment, it threw off* 

 its load with a jerk, and quite disengaged it from the nest It 

 remained in this position for a short time, feeling with the extremity 



1 Lottinger published in 1775 his Mtmoirr vur It coucov, which contains no indication that 

 he realised there was ejection by the young cuckoo. It is largely concerned with the 

 behaviour of birds when eggs of other species are placed in their nests. Lottinger's observa- 

 tion* were corrected and supplemented by those of Paul Leverkuhn in hi* Frmtd* Eitr itn AVf . 

 1801. A copy both of the Mtntoir* and a German translation of it are to be found at the British 

 Museum. A copy of the //tstotn* du coucou tCBvropt is in the Newton Library at the Cambridge 

 Zoological Museum. 



* PHOofophifal Tratunrtion* of th* Royal Society of London, vol. Ixxviii., 1788. BMW. The 

 account, entitled " Observations on the Natural History of the Cuckoo," is in the form of a letter 

 written by Jenner on December 27, 1787, and read to the Royal Society by John HunU-r on 

 March 18, 1788. It contains other interesting observations on the cuckoo besides the one 

 above referred to. 



