MEANING OF JAGUAR AND LEOPARD ROSETTES 123 



also given five little specks on each central plate, to assimilate them 

 with some of the Jaguar rosettes, but there may have been many 

 more, as in the plates of Tolypeutes. 



All this imaginary restoration, however, was hardly necessary, 

 as in Fig. 62 {c\ which is part of the carapace of a Glyptodont, 

 shows an almost identical arrangement of bone-rosettes. 



Reference to Figs. 61 and 62 will show how various the 

 number of small plates is which encircle the bigger central plate. 

 In some cases the inference would be that the smaller plates have 

 occurred to completely fill in vacant spaces left by the larger and 

 more solid plates, and thus leave no part of the skin unprotected. 

 Where great flexibility is needed, as between the bands of Arma- 

 dillos, it is obvious that plates would be an encumbrance, and simple 

 elastic skin preferable. 



The dissociation of the plate-rosettes, with intervening elastic 

 skin, would have admitted of freer movements — a feature of great 

 importance in the struggle for existence — than would have been 

 possible in the dish-cover solid carapace of a Glyptodont. 



This dissociation of plate-rosettes is not simply a hypothesis, for 

 we see it actually occurring on the abdomen of the Great Armadillo 

 {Priodontes maximus)^ which in that region has rows of separate 

 rosettes, composed of minute plates, while the carapace is formed 

 of bands of squarish plates, with intermediate skin commissures, 

 like those shown in Fig. 64 {b). 



It may perhaps be objected, that if the plate-rosettes could be 

 dissociated bodily, the component smaller plates could also be dis- 

 sociated. Just so, and that is what may have occurred in the ances- 

 try from which the Cheetah has descended. Its plate-impressions, 

 large and small, though probably much modified, are scattered all 

 over its skin. 



^ Edinburgh Museum of Science and Art. 



