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because they fail to aid in armor productions. To any later tendon ossification so 

 pronounced in Ceratopside as well as in various armorless Dinosauro the terna subdermal 

 might better apply. 



In any case however, the accurate study of the early embriology of Dermochelys 

 must, afford data of primary value in determining the homology and nature of the 

 initial armor-forrning stratum in the Reptilia. Theoretically, it would seem that in its 

 earliers stages this stratum may be traced back to a single layer or else a doublé 

 layer of cells capable of rapid ectal and ental bone production. 





