24 STUDIES IN THE EVOLUTION OF ANIMALS 



be, after all, consolidated Leopard rosettes further modified into 

 circular spots. 



On the other hand, Fig. 12 shows conditions which would 

 suggest that it is the enclosed spaces of the Jaguar rosettes which 

 become the large round spots of the Cheetah, while the specks are 

 the dissociated rings of spotlets ; only the enclosed space in this case 

 would be, as I said, changed from irregular brown to circular black. 



A very young Cheetah in the Natural History Museum (case 16 



Gueparda jubata], from the Cape of Good Hope, shows a very 



interesting variation. It is brown with faint spots, but what is 



still more curious is the fact that its 

 o S? 

 o " o ^b^ back is grey like that of a badger ! 



It may be of some interest to show 

 ^ o 



how much variation the Jaguar rosettes 



FIG. 13. Rosettes from a can undergo. Fig. 13 is taken from 



picture of the Jaguar in Griffith's j pictured in Griffith's Cuvier. 



C^lvlcr t p. 455, vol. n. 



They may, perhaps, be closely matched 

 from groups on the Cheetah skin of Fig. 1 1 . 



This much is clear to me, that the Cheetah and the Leopard 

 are closely allied in habits and structure, and their spotting, how- 

 ever modified it may have become, must have had one ancestral 

 origin, not necessarily of course from the same individual, but 

 from the same species of ancestor ; and that the difference in the 

 existing animals comes from microscopical changes in the nerve- 

 centres, which would result in pronounced differences on the skin. 



The student of animal markings would do well to study, as 

 a previous training, the many-synonymed orchid Odontoglossum 

 crispum, and others of the same genus. Nothing is more interest- 

 ing than a review of the variations of blotches on the petals of this 

 genus. There are blotches of various sizes and forms ; there are 

 cross-bars ; in some varieties there are single little spots on each 



