MEANING OF JAGUAR AND LEOPARD ROSETTES 105 



may yet teach us a great deal about animal coloration and mark- 

 ings. The markings of the Jaguar, however, I think are due, not to 

 the action of light, ibut to a totally different cause, as I hope to show. 



Mr. Poulton ^ considers it proved that the white hair of certain 

 Arctic animals is caused by the low temperature of the winter. 

 Quoting from Mr. Welch, he says that in the American Hare, on 

 the approach of winter, the dark hairs of the old coat turn white, 

 commencing either at the tip, the middle, or the base of the hair, 

 and that in addition there is a new winter coat coming up of an 

 entirely white colour. And at p. 103, Mr. Poulton says that the 

 young of the Arctic Hare are born grey, and turn white at their 

 first winter. 



All this does not affect the fact that in dappled grey Horses the 

 spots are white, in dappled brown and dun Horses the spots are 

 lighter than the ground colour, in roans they are black, and in 

 strawberry roans they are bay or brown. Moreover, I have seen a 

 grey Horse with tan-coloured spots.^ So with many other animals 

 that might be quoted. It is clear that in these cases temperature 

 can have nothing to do with the difference in coloration, and we 

 have to search for other causes to account for the coloration of 

 certain animals, and more especially for those extraordinary mark- 

 ings we see in the Jaguar, the Leopard, the Cheetah, the Tiger, the 

 Zebra, and so many other mammals. 



A study of the rosettes in Fig. 59, and many others that can be 

 seen on skins, makes it evident to me that, whatever may be the 

 initial atomic nervous influence which produces these variations, 

 they result in two sets of modifications, (a) a fusion of some or of 

 all the encircling spots, and often in an obliteration of the enclosed 

 space ; or {b) a dissociation of the encircling spots, and perhaps 

 even a scattering of the enclosed specks. 



^ Colotirs of Animals, p. 95. ^ See Appendix C. 



