2G0 



ANNALS NEW YORK ACADEMY OF SCIENCES 



They are far more primitive and nearer to the generalized eutherian 

 type; but they show certain unique Xenarthrau peculiarities in foot- 

 construction and in tiie pelvis, and the dentitioji in ilie two known phyla 

 progressively evolves on lines leading towards, although not into, the 



PHYLOGENY OF THE EDENTATES 



ARMADILLOS 



ANTEATERS TREE-SLOTHS 



Fig. 30. — Distribution and phylogeny of Xenarthra and Twniodonta 



The aberrant North American groups appear to be relicts indicating a northern origin of 

 the Xenarthra, but the evidence is not conclusive. 



