CHAPTER X 



REPTILES IN THE MAKING 



Young reptiles as they step out from the shell are, so to 

 speak, adults in miniature ; whereby they differ con- 

 spicuously from the mammals and birds, which pass through 

 a more or less extended infantile period. ^ But there are 

 exceptions to every rule, and the tortoise-tribe are among 

 these. If it were not for the fact that the tortoise is num- 

 bered among our " familiar beasts," we should regard it as 

 one of the most remarkable, if not the most remarkable, of 

 backboned animals, since it alone among its peers lives 

 inside its skeleton, so to speak, just like the beetle and the 

 butterfly, wherein, as everybody knows, the hard parts 

 which afford attachment and leverage for the muscles 

 which are responsible for movement, are outside, and often 

 tinctured with all the hues of the rainbow. But in the 

 case of the tortoises and turtles this anomalous condition 

 is confined to the trunk alone, which is encased within 

 a bony, horn-ensheathed shell. How this extraordinary 

 condition came about is revealed in part by a study of 

 young tortoises and in part by what is revealed in the 

 case of that strange creature the Leathery Turtle or 

 Huth. 



In this last-named species the great back-shield is 

 formed of a number of small more or less circular bony 

 plates, interlocking by means of jagged edges : the whole 



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