892 JOURNAL, BOMBAY NATURAL HISTORY SOCIETY, Vol. XVTI. 



Knowledge as to the eggs of other species of Indian Cuckoos is not yet 

 sufficient to allow of generalization. 



On the whole, therefore, Indian Cuckoos would appear to adapt 

 themselves more or less to producing eggs which to some extent resemble 

 those of the birds they select as foster-parents to their young. How this 

 adaptation is evolved is difficult to guess at. We see birds sitting in 

 complete happiness on eggs at least four times as big as their own pro- 

 ductions and as little like them in shape and colour as it is possible to 

 conceive. Why, then, the necessity for adaptation ? Presumably it 

 must hd admitted that here and there birds are possessed of superior 

 intellect sufficient to enable them to see the differences between their 

 own eggs and the imposters, and on seeing such differences destroy the 

 latter. In this way such Cuckoo's eggs as approach most nearly in 

 colouration to those of the foster-parents would survive, whilst those 

 which greatly differ would gradually be eliminated. 



In Professor Burnett's first article quoted, he says he thinks it more 

 probable that the foster-parent turns out the young than that the 

 young cuckoo itself does this. It has, however, been practically 

 ascertained for certain that it is the yuung Cuckoo who is the culprit, 

 and he has been seen more than once in the very act of ejecting his 

 unfortunate fellow nestlings. Moreover, the young Cuckoo has been 

 especially built by nature to perform this act of ejectment and has his 

 back suitably formed and is given powerful legs and thighs as a nest- 

 ling, though the latter develop but little afterwards. As to his opinion 

 that the Cuckoo generally deposits its eggs in a nest already occupied, 

 this is probably correct. In many instances this year the Cuckoo's egg- 

 has been found deposited on the top of the fosterer's, and though the 

 Cuckoo's egg has sometimes been found to be fresh whereas the others 

 showed more or less signs of incubation, the reverse has been ex- 

 tremely rare. 



Caccomantis merulinus. 

 The Rufous-bellied Cuckoo. 



1 have had two very remarkable eggs sent to me which I would attri- 

 bute to this bird if they are Cuckoo's eggs at all. 



These two eggs and another of the same description were taken in 

 May this year (1 'JUG) in the Gooma Reserve, Goalpara, Assam, and 

 were all found in the nests of aEthopyga sehcrue, the Himalayan 

 Yellow-backed Sun-bird. The eggs, which were sent me — one by 



