PLATE 7 



TYPE SKULL AND LOWER JAWS OF PARAHIPPUS NEBRASCENSIS PRIMUS OSBORN. 



All figures one-half natural size. 



Amer. Mus. 13770, type. This skull belongs to a fully adult male and consequently shows very clearly the dis- 

 tinctive characters of the Parahippus skull stage. The crochet is well developed on the superior molar teeth. The hypo- 

 style is simple and does not show the progressive hypostyle fold, the pli hypostyle. 



This male skull, which was found in the Lower Miocene of the Upper Harrison near Agate, Nebraska, is more pro- 

 gressive than the type skull of P. ncbrascensis Peterson, which belongs to a female. In this male skull the facial region is 

 relatively longer. 



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