396 Mr. E. C. Stuart Baker oii the Evolution of 



eggs may be accepted as being completed ; and it will be seen 

 that the process of ada2)tation has evolved an egg which agrees 

 most closely with the eggs of Garrulax moniliger, G. austeni and 

 G. striata, the normal foster-parents of the young Coccystes. 

 The rare occasions in which they are not placed in the nests 

 of Laughing-Thrushes -which lay blue eggs are probably 

 mistakes, being so placed by the Cuckoo before there are 

 any of the fosterers^ eggs in the nests, or because, though 

 there are eggs, she herself cannot distinguish their colour. 



Cuccystesjacobinns,i\ivo\v^\\o\\t the greater part of its range, 

 selects the same nests as docs Hierococcyx vurius, and though 

 their breeding-season is not the same, there is an overlapping 

 period when eggs of tlie Hawk-Cackoo, the Pied Crested 

 Cuckoo, and the foster-parent may be found iu the same nest, 

 the majority quite indistinguishable one from the other; all 

 are blue, and all of much the same size, texture, and shape. 



The smallest of our Indian parasitic Cuckoos, of the genus 

 Chry so coccyx, also give us a most beautiful example of 

 adaptation. We have no oviduct specimens of these birds' 

 eggs, but to Messrs. A. Primrose and Chas. M. Inglis we 

 owe an equally good proof of identity. These two gentlemen 

 discovered a place where the little Sun-bird ^'Etliopyga 

 seheri(B was breeding very freely, and iu many of the nests 

 they found that there was one egg exactly simitar in colour 

 to the Sun-bird's egg, but decidedly larger. Specimens were 

 sent to me, and in response to my request an egg was left 

 in situ and hatched ; when, later, the almost full-grown bird 

 was sent to me, it proved to be a specimen of C. maculatus. 



Here we have a small metallic-coloured Cuckoo depositing 

 its eggs similar, in all respects but size, to those of the 

 Sun-bird, in the nest of a bird the cock of which is also 

 metallic-coloured. 



Since this discoverv was made I have obtained other egss 

 of this and of the Violet Cuckoo (C. xanthoi'hyncJms) in nests 

 of Arachnotliera loncjirostris. with eggs of which they agree 

 fairly well, and in the nests of Orthutoinus and Cisticola, with 

 eggs of which they do not agree at all. The proper fosterers 

 for this Cuckoo are undoubtedly birds of the genns^Et/iopyr/a, 



