PROTECTIVE COLOURING IN ANIMALS 311 



ment with the object, realise that what is a mark of 

 distinction or recognition when seen at a few inches' dis- 

 tance may be an illusive and obscuring colour-scheme 

 when seen at a distance of some feet, and in natural and 

 habitual surroundings. It is not unlikely that we shall 

 arrive at definite knowledge of the psychological "sight 

 interpretations " of animals by a further study of this 

 subject. It is in the highest degree probable that the 

 retinal picture produced in an animal's eye by certain 

 spots of colour, shade, and light exhibited by another 

 animal, are not interpreted by the receptive animal in the 

 same way as they would be by a scrutinising, inquiring, 

 reasoning man, even one who is what we call a "savage." 

 Moreover, though many English naturalists have travelled 

 and seen " life and light " in the sunny regions of the 

 earth, there are few students of the colour-markings of 

 animals in our museums, especially in great cities, who 

 have adequate experience of what colour-markings really 

 can effect in the way of concealment and illusion when 

 light and surrounding objects are as they are, in the 

 tropics or sub-tropical regions. It is a fashion nowadays 

 in the best-provided museums of natural history to exhibit 

 stuffed beasts, birds, and insects in what are called " their 

 natural surroundings." The fatal objection to such ex- 

 hibitions is that were the beasts, birds, and insects placed 

 in their most usual " natural surroundings," they would be 

 invisible ! 



It is the merit of Mr. Thayer to have drawn attention 

 to these considerations, and to have carried out some 

 interesting demonstrations of the more frequent signifi- 

 cance of colour-markings as means of concealment and 

 illusion than had been recognised before his work. At 

 the same time, it is not possible to consider the yellow 

 and black livery of wasps, of certain evil-tasting grubs, 

 and of poisonous salamanders as anything but a " danger- 



