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IO7 



from the shape of the second phalanx it may be confidently inferred that the 

 extraordinary claw-like form characteristic of Agriochcerus had not yet been 

 developed, at least not in any such degree. It would be most important to 

 learn whether the unguals showed any tendency towards the assumption of 

 the claw-shape, but this must await future discovery. 



In the following table measurements of Protagriochcerus annectens and 

 Agrioclicerus latifrons are given together for purposes of comparison. 



MEASUREMENTS. 







Protagriochcerus. 



Agriochcerus. 



Astragalus, length .... 





O.031 



" width proximal trochlea 



.015 



.OI7 



Calcaneum, width distal end 



.006 



.007 



depth " 





.OI4 



.OI9 



Cuboid, height of dorsal face 





.OI4 



.OI4 



width 





.OI25 



.OI 5 5 



" thickness 





.Ol6 



.023 



Navicular, height 





.OIO 



.009 



" width . 





.Oil 



.017 



" thickness 





.OI7 



.021 



Second phalanx, length 





.OI7 



.017 



" width proximal end . 



.OO9 



.OO95 



" " distal end 



.0075 



.008 



" thickness proximal end 



.00S 



.OIO 



" " " distal 



end . 



.0075 



.008 



The single species of Protagriochcerus at present known may be called 

 P. annectens, sp. nov., and in the absence of other species with which to com- 

 pare it its definition can be formal only. This may be taken, first, from the 

 size as given in the various tables of measurements, and, secondly, from the 

 simplicity of the premolar teeth. 



The Taxonomic Position of Protagriochcerus. 

 This genus is not yet sufficiently well known to render its systematic 

 position and its phylogenetic significance clear, though what little we already 

 know concerning it is highly suggestive. The dentition, and especially the 

 upper molars, leads us almost irresistibly to the conclusion that Protagrio- 

 chcerus is ancestral to Agriochcerus, and this conclusion is further confirmed by 

 the character of the tarsus. This differs from that of Protoreodon in very 

 much the same way as the tarsus of Agrioclicerus differs from that of Orcodon. 



