GREGORY: NOTIlARCrUS, AN AMERICAN EOCENE PRIMATE 



103 



adduction of the hallux, which thus could not be drawn in parallel to the other digits but always diverged 

 markedly from them. 



The shaft of the first metatarsal below the proximal expansion narrows rapidly, the anterolateral 

 border being nearly straight, the posteromedial deeply incurved. The shaft is moderately short. To- 

 \\-ard the distal end it again becomes very asymmetrical. The anterolateral border of this swelling is 



.■) (I 7 S 



1 2 ;j 4 



Fig. 2)). ( 'oini)iirati\ t' scries: riglit liallux (if A 'vf//a;r///.s', Ij iiiur, Crhn.^, Macavus. Natural si/A'. 



1. Notharctusosbonii. Amer. Mus. No. 11474. '■>. Cihiixluipttli iinis. Amor. Mus. No. 1401G. 



2. Lemur mongoz. Amer. Mus. No. 22886. 4. Mitnu-ii:< ii< iii<sininis. .\.iner. Mus. No. 14012. 



5, 6, 7, 8. Same series, to]) view. 



roughened for the internal lateral ligament, which connects the first metatarsal with the proximal phalanx. 

 The posteromedial border of the lower part of metatarsal I bears a rounded pit i)robal>ly for the external 

 lateral ligament, which also passed to the proximal phalanx. 



The extreme distal end of metatarsal I bears a convex facet for the first phalanx ; this facet is slightly 

 extended on to the dorsal surface to permit extension of the hallux. 



The {)lantar aspect of the distal end of metatarsal I bears two concave facets, or grooves, separated 



