EDWAKD D. COPE. 75 



lartlira have five digits on both feet, and they are planti- 

 grade. This character is retained in their descendants 

 of the lines of Anthropoidea, Quadrumana and Hyra- 

 coidea, also in the Bunotheria, Edentata and most of the 

 Rodentia. In the Amblypoda and Proboscidia the palm 

 and heel are a little raised. In the Carnivora and.Di- 

 plarthra the heel is raised, often very high, above the 

 ground, and the number of toes is diminished, as is well 

 known, to two in the Artiodactyla and one in the Peris- 

 sodactyla. (B) The tarsus and carpus. In the Condy- 

 larthra the bones of the two series in the carpus and 

 tarsus are opposite each other, so as to form continuous 

 and separate longitudinal series of bones. This continues 

 to be the case in the Hyracoidea and many of the Quad- 

 rumana, but in the anthropoid apes and man the second 

 row is displaced inwards so as to alternate with a first 

 row, thus interrupting the series in the longitudinal di- 

 rection, and forming a stronger structure than that of 

 the Condylarthra. In the Bunotherian rodent and eden- 

 tate series, the tarsus continues to be without alternation, 

 as in the Condylarthra, and is generally identical in the 

 Carnivora. In the hoofed series proper it undergoes 

 change. In the Proboscidia the carpus continues linear, 

 while the tarsus alternates. In the Amblypoda the 

 tarsus alternates in another fashion, and the carpal bones 

 are on the inner side linear, and on the outer side alter- 

 nating. The complete interlocking by universal alterna- 

 tion of the two carpal series is only found in the Diplar- 

 thra. (C) As to the ankle-joint. In most of the Condy- 

 larthra it is a flat joint or not tongued or grooved. In 

 most of the Carnivora, in a few Rodentia, and in all Di- 

 plarthra, it is deeply tongued and grooved, forming a 

 more perfect and stronger joint than in the other orders, 

 where the surfaces of the tibia and astragalus are flat. 

 (D) In the highest forms of the Rodentia and Diplarthra 

 the fibula and ulna become more or less coossified with 



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