124 



STUDIES IN THE EVOLUTION OF ANIMALS 



FIG. 71. The Hairy Armadillo (Dasypus vil- 

 losus], Natural History Museum. 



In snakes we see closely fitting scales, but in the Python, and 

 in the expanded hood of the Cobra, the scales are scattered over 

 the skin, with intervening spaces without scales. So that stretch- 

 ing of the skin may have had something to do with the scattering 



of the rosettes, whether as 

 dissociated bone-plates or 

 dissociated pigment-spots. 



There is another feature 

 in the Leopards which is 

 worthy of notice. On their 

 legs there are transverse 

 rows of small spots. These, in my view, are impressions left by 

 transverse rows of small plates, not unlike those which we see on 

 the legs of an existing Armadillo, shown in Fig. 71. 



We now begin to get a sort of * moral conviction ' that the 

 transverse stripes on the legs of Tigers, and other Cats, are due to 

 ancestral rows of spots like those on the legs of Leopards, and these 

 in turn are due to the fact that their armoured ancestors had scales 

 or plates there, similarly disposed. 



In the Hairy Armadillo and others no doubt the leg-plates are 

 in process of extinction. As the animals can roll themselves up in 

 their banded carapace, their leg-plates have become superfluous, 

 and are doomed to extinction. 



Taking then everything into consideration, I think it will be 

 found difficult to escape from the conclusion that the markings of 

 the Leopards are inherited from ancestral plate-impressions of some 

 extinct Glyptodontoid form, and have not been evolved by a process 

 of natural selection. 



It is a wonder to me that in the Jaguar so much likeness to 

 ancestral bone-plates still remains as to enable us, through these 

 hieroglyphics, to read the story of its descent. But for these 



