LIFR-HI6T0RT OF CUCULUS CANORUS. . 199 



in the nest varies greatly. As shown by Hancock (IST.H. Trans. 

 JSTorthumb. and Durham, viii.) almost the whole eJutch may be 

 undisturbed. 



Although this article has been written to accompany an exhi- 

 bition of eggs, and to bring out certain points which have 

 received insufficient attention, without the intention of criticizing 

 the work of others, it is impossible to end without mentioning 

 the standard paper on Cuculus canorus by Dr. Eugene E,ey, 

 published at Leipzig in 1892 as No. 11 of Marshall's '■ Zoologische 

 \^ortrage.' This laborious and elaborate piece of work may be 

 taken to comprise all that was known up to that date of the 

 bird's nesting-habits, and contains long dissertations on the 

 number of eggs laid in a year, the date of deposition, their size, 

 weight, texture, and the composition of the shell, with lists of the 

 foster- parents, the number of their eggs suffered to remain in the 

 nest during incubation, and so forth. Tables and even graphs are 

 given to elucidate the text, and, finally, full details of the immense 

 number of specimens accumulated. 



Admirable, however, though this paper is, it fails in the points 

 upon which I am now insisting. (Sixteen out of Rey's seventeen 

 conclusions may be taken as correct, but when he states that most 

 hen Cuckoos lay in the nests of definite species of foster-parents, 

 except on rare occasions, his theory runs counter to experience. 

 Of course the objection raised is only to his use of the word 

 "most," and would have failed if he had said "not uncommonly." 



Again, he tells us that the bird generally lays her eggs in the 

 same locality or even spot, that is, that she does not wander far 

 in the nesting- season. If he had only been able to add the 

 expression " in successive yeai's," he would have anticipated my 

 observations, made over a longer period than his. 



