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NATURE-STUDY REVIEW [10:6— Sept., 1914 



able to swim and walk quite as well as a perfect specimen ; when 

 placed on its back on a smooth, level surface, it was to be observed 

 that it had already learned the trick of smartly righting itself by 

 perhaps a somewhat more than usual vigorous use of the two limbs 

 of either side. The dermal scutes covering the osseous carapace 

 were normal in number and arrangement and modelled perfectly 

 upon the enlargement, even the paler shade of their margins being 

 in evidence, and exhibiting no more distortion than was necessary 

 in order to accommodate their several outlines to the increased area 



Reduced One-half 



Figs. 3, 4 and 5 



Photo by Author 



to be covered over (Fig. 2, a). Viewed from below (Fig. 4), this 

 turtle appeared to be normal in every particular, and when so 

 regarded, the presence of the great hump on its back would never 

 be suspected. 



It exhibited no evidences whatever of having received any 

 injury or abuse that might account for its extraordinary shape, the 

 animal being in all other respects a remarkably pretty one, with all 

 its markings very brilliant and deep-tinted. 



The reason for such a deformity defied all speculation, for there 

 was no external evidence whatever of what might have given rise to 



