The Zoologist— March, 1868. 1113 



Brehm, Glogcr, von Homeyer and others, and I may add that this 

 point was equally well known to our British ornithologists as well.* 

 But Dr. Bahlamus seems to have been the first to suspect that at the 

 root of this striking phenomenon there was a fixed law, perhaps a law 

 which might be discoverable ; and his suspicions in this direction 

 having been aroused, he proceeded to pay diligent attention to the 

 subject. To this end-he not only made most careful personal observa- 

 tions, but, by means of oological correspondents in various parts of 

 Germany, collected a large series of facts bearing upon the matter, 

 which were convincing to his own mind, — convictions which seem to 

 have been shared iu by many of the leading ornithologists of Germany. 

 I will not weary the patience of members of this Society by taking 

 them through the several instances which Dr. Baldamus details; but 

 pass on at once to the results he arrived at, merely remarking, by the 

 way, that he followed up his investigations with such earnest zeal, 

 that when he wrote his paper he had before him no less than one 

 hundred cuckoo's eggs, special care being taken to ascertain accurately 

 from the nest of what particular species every one of these eggs was 

 taken. 



Now the first thing which Dr. Baldamus established to his own 

 satisfaction, by means of these repeated observations, was, that the 

 cuckoo lays its eggs in the nests of no less than thirty-seven species, 

 including not only every species of chat, warbler, wagtail, pipit and 

 lark, but even exceptionally certain of the grain-eating finches and 

 buntings; these exceptions being doubtless in cases only where the 

 cuckoo was deprived, by some accident, of the nest she had selected 

 for her egg, and which when ready to be laid she was obliged to 

 consign to the care of the best nurse she could find at short notice. 

 To this seeming inconsistency on the part of the parent bird, I may, 

 however, add that the grain eating species have been known to bring 

 up young cuckoos ; and the explanation is, that even the hard-billed 

 birds are accustomed to feed their young, at any rate at first, with 

 insects. 



From the thirty-seven species alluded to above, which have been 

 ascertained to act as foster-parents of the young cuckoo, Dr. Baldamus 

 enumerates no less than twenty-eight, to whose several eggs he affirms 

 the cuckoo will assimilate her egg in colouring; and this he then 

 proceeds to prove from the specimens lying before him, and which 



* Wood's ' Illustrated Natural History,' vol. ii. p. 572. 

 SECOND SERIES — VOL. III. N 



