26 STUDIES IN THE EVOLUTION OF ANIMALS 



young one (a) has its white spots close to each other, in some parts 

 almost coalescing into blotches. Then as the animal grows the 

 spots become more distinct, and in the adult they are separated by 

 long intervals, as shown in (). 



However this may be, we cannot ignore the fact that the whole 

 physiology of the skin in Mammals, with its colourings and mark- 

 ings, is under the control of the nerve-centres (perhaps as much as 

 electro-plating is under the control of the battery or dynamo), and 

 these again are under the various influences of heredity, age, varia- 

 tions of temperature, climate, composition of the blood, and other 

 surroundings, of which we know yet too little. 1 



In the various kinds of Leopards we see that not only the 

 rosettes differ, but also the spaces between them differ much. 



These inter-rosette spaces run into each other, and form a 

 sort of broad reticulation which is the ground-colouring of the 

 skin. 



The Leopard of Kismaya, British East Africa, 2 has its rosettes 

 much closer than those of the Indian Leopard or of the American 

 Jaguar, so that it seems much darker than they. The comparative 

 smallness of this animal, supposing the number of rosettes to be 

 equal, may, I think, sometimes account for the compactness of the 

 rosettes, as well as for their elementary spotlets. 



At Mr. Rowland Ward's establishment, Piccadilly, I was shown 

 a very small foetal Leopard, that is, in a stage before birth. It was 

 closely spotted all over, but none of the spots were ocellated. 

 Another young Leopard, but older than the preceding, had a com- 

 mencing faint ocellus in some of its spots. On the other hand, a very 



1 Orchids seem to undergo similar alteration in the spotting of their flowers, without 

 any nervous influence that can be detected. Yet there must be some means of com- 

 munication in the Dioncca between the bristles and the hinges of the leaf-blades, 

 analogous to nervous or electric communication. 



2 In the Zoological Society's Gardens. 



