MEANING OF JAGUAR AND LEOPARD ROSETTES 117 



body and from its ruler the brain, the rosettes of the Leopards may 

 be quoted. Who can tell how many millions of generations have 

 elapsed since the ancestors of these animals and their congeners 

 threw off their calcareous carapace, and adopted a masquerade of 

 pigment-rosettes instead ? Yet to this day this masquerading goes 

 on in the Leopards and Jaguars, in their black varieties, as well as 

 in the Snow Leopard. They are unable to shake off this pigment 

 dress inherited from a calcareous carapace, although their habits 

 and customs, their entire skeleton and teeth, have undergone great 

 modifications. 



Fig. ^t. — Bone-rosettes from the carapace of the Glyptodon, Natural History Museum, 

 [a] partially fused rosettes from front of carapace, [b) distinct rosettes from side of carapace. 



It must not be supposed, however, that bone-rosettes are not 

 subject to fusion and other modifications. Fig. 6] {a) shows two 

 bone-rosettes with a tendency to approximate and partially fuse ; 

 while (/;) shows them quite distinct, and are given for comparison. 



Hitherto I have traced the similarity of the Jaguar rosettes with 

 the bone-rosettes of Glyptodontoid and Armadilloid animals which 

 are also mammals. But chi cerca trova ! Strange to say, this 

 similarity can be traced much further down in the scale of life, 

 and therefore much further back in time. Among the Chelonians 

 we seem to find the identical mould from which the Glyptodon 

 derived its bone-rosettes. 



The Leathery Turtle {Dermochelys coriaced) has thin mosaically 



