. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology. 92 Museum of Comparative Zooloi;y, Vol. 134, No. 3 more horizontal!>' oriented; posterior lunar- magnum facet relatively smaller. Cunei- form with posterior part of proximal surface lower, resulting in a more distally located pisiform facet. Trapezium relatively higher. Trapezoid relatively shorter (anteroposte- riorly) and higher, with less of a posterior process. Magnum with a relatively lower and wider anterior face and a shorter and less pointed posterior process; magnum- unciform articulation relatively higher
. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology. 92 Museum of Comparative Zooloi;y, Vol. 134, No. 3 more horizontal!>' oriented; posterior lunar- magnum facet relatively smaller. Cunei- form with posterior part of proximal surface lower, resulting in a more distally located pisiform facet. Trapezium relatively higher. Trapezoid relatively shorter (anteroposte- riorly) and higher, with less of a posterior process. Magnum with a relatively lower and wider anterior face and a shorter and less pointed posterior process; magnum- unciform articulation relatively higher, but lacking a separate posterior facet; magnum- second metacarpal facet higher proximodis- tally. Metacarpals relatixely shorter and wider. The main difference between the front foot of and that of Ilcptodon is in the radio-carpal joint. The truncation of the posterior end of the scaphoid and lowering of the posterior half of the lunar produces a posteriorly-shortened articulation between the radius and the scaphoid and lunar. This difference, plus the lower pisiform facet on the cuneiform, suggests greater freedom for flexion at this joint in Tapirus. The lat- eral extension of the proximal surface of the scaphoid behind the proximal facet of the lunar strengthens the scapho-lunar articula- tion and also provides additional support for the radius (possibly to compensate for the shortened radio-lunar articulation). Most of the other differences listed above are either related to the modification just discussed or, like the more horizontal lunar- magnum facets, result from the greater weight of Tapirus. The manus of Frotapirus was described and figured most recently by Scott (1941, pp. 756-758, pi. 80, fig. 2), based on a late Oligocene specimen (AMXH 662). It is generally quite similar to the manus of Tap- irus, but slightly more primitive in the following features: scaphoid and trapezoid relatively longer anteroposteriorly; posterior process of lunar and cuneifonn
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