Ill [Vol. XXXV. 



smell, and taste, how was it that the foster-parents could not 

 do the same? 



He further remarked that parallel evolution was a con- 

 stant cause of similarity between species of different genera, 

 a point which did not seem to have been considered by 

 Mr. Swynnerton at all. 



The Rev. F. C. R. Jourdain said that, from observations 

 made in the field in England, the egg-eating birds showed 

 no discrimination of colour, but devoured all kinds found by 

 them. Thus the Hooded Crow has been known to devour 

 the eggs of species differing widely in colour and markings, 

 such as those of the Red Grouse, Wood-Pigeon,- Cormorant, 

 Black-throated Diver, Heron, Gulls, and many others. 

 Experiments made under purely artificial conditions formed 

 a very uncertain foundation for theory, unless corroborated 

 by field-observation. 



Mr. D. Seth-Smith referred to the semi-luminous, bead- 

 like, blue warts which are present on the sides of the base of 

 the mandibles in the nestlings of certain species of birds, 

 such as the Gouldian Grassfinch {Foephila mirabilis) and 

 the Parrot-Finches (Eryth-ura). He remarked that these 

 appeared to be necessary in order to indicate to the 

 parent-birds where to place the food. When feeding the 

 parent stood in the entrance-hole of the nest, excluding 

 almost all light, and in this position the nestlings were 

 nearly invisible, but when their mouths were opened these 

 could be readily located by the presence of the blue beads 

 which were placed, as it were, at each corner of a square. 



In the discussion which followed, the Chairman, 

 Dr. Hartert, Mr. PiCRAFT, and several other members 

 took part. 



In reply to various criticisms, Mr. Swynnerton added 

 that_, in thinking over the points which had been raised, he 

 felt that mimicry in Cuckoos^ eggs might often well have 



