452 JOURNAL, BOMBAY NATURAL HISTORY SOCIETY, Vol. XV. 



eggs almost invariably fulfil this condition is, I think, well esta- 

 blished. The result is of course due to the action of natural selection. 

 The eggs lie exposed, and those which least resemble their surroundings 

 will be the ones most likely to be devoured by animals. 



There remains the third class of eggs. This comprises those laid in 

 nests, but not in the dark. There is no use in such eggs being white ; 

 for, no matter what their colour be, the bird to which the nest be- 

 longs will have no difficulty in seeing them. It is also, I submit, quite 

 unnecessary for them, hidden away as they are in the nest, to be of the 

 same colour as either the lining of the nest or the surrounding 

 foliage. It is of importance to the species that the nest should be well 

 concealed, or domed, or otherwise rendered difficult of access. It is upon 

 this that the safety of eggs depends and not on their colour. When once 

 a nest containing eggs is discovered by a crow, a tree-pie or a lizard, all 

 hope for the eggs is gone. The bird or repiile having made such a find 

 will not leave it until it has made sure it contains no eggs. In order 

 that the eggs In^i nest should escape the notice of such vigilant creatures 

 it would be necessary for them to be so coloured as to be indistinguishable 

 except upon the most careful scrutiny from the lining of the nest, or for 

 the owner of the nest, on leaving it, to invariably cover them up by 

 making a false bottom to the nest. This latter precaution would be a 

 far greater protection than any colouring. 



The idea of a lizard which has climbed up into a bulbul's nest in a 

 croton plant being deceived by the markings on the eggs into thinking 

 that the nest is empty is ludicrous. Yet the theory of protective colour- 

 ation demands that the eggs shall be coloured so as to be distinguishable 

 only with the utmost difficulty from their surroundings. 



It would therefore seem that such eggs are neither protectively 

 coloured nor subject to the action of natural selection. I belie\e that they 

 are in a state of panmixia, that to them one colour is as useful as another, 

 that among them variation and heredity are allowed free play. We 

 know how in animals under domestication all manner of colours arise 

 apparently without any selection. I believe that eggs laid in nests are 

 in a similar condition, that variations in colour or markings are neither 

 harmful nor beneficial. If this be so, it is obviously futile to endeavour 

 to discover protective resemblances in the markings of eggs ; we should 

 rather regard birds' eggs as perhaps the most convenient and interesting 

 material at our disposal for the study of variation. 



