2O4 



PATAGONIAN EXPEDITIONS I PALEONTOLOGY. 



The ungual phalanx of the hallux is considerably shorter than that of 

 the pollex, but broader and thicker. Digit II has a very much larger 

 ungual, which is shorter and more massive and is more strongly decurved 

 than the corresponding claw in the manus, and the distal cleft is more 

 extended along the dorsal border. The third digit has a still longer and 

 heavier ungual, the proximal end of which is extremely massive ; owing 

 chiefly to the size of this ungual, digit III is considerably longer than II, 

 though the difference is decidedly less than in Nothrotherium. 



As a whole, the pes is considerably larger than the manus, especially 

 exceeding the latter in the massiveness of its component parts. 



MEASUREMENTS. 



Calcaneum, length 075 



width of proximal end 065 



" " " distal end 038 



Astragalus, length 042 



" width of trochlea 029 



" " distal end 023 



" thickness of distal end 016 



Navicular, length on tibial side 016 



" fibular side 005 



" width 026 



Metatarsal I, length 020 



" proximal width oio 



" distal width 008 



Metatarsal II, length 025 



" " proximal width 017 



" " " thickness 016 



" " distal width 015 



" " " thickness 020 



Metatarsal III, length 026 



" proximal width 023 



thickness 027 



" " distal width 017 



" " " thickness 023 



Metatarsal IV, length 055 



" " proximal width 014 



" " " thickness 025 



" " distal width 014 



" " " thickness 023 



Metatarsal V, length 045 



" " proximal width ? .027 



" " " thickness 017 



Metatarsal V, distal width 013 



" " " thickness 014 



First phalanx, digit I, length 019 



" " " " proximal width.. .010 



" " " " thickness. .0135 



" " " " distal thickness . .0085 



First phalanx, digit II, length 016 



" " " " proximal width. .013 

 " " " " proximal thick- 

 ness 019 



" " " " distal thickness. .013 



" " " III, length 019 



" " " " proximal width. .017 

 " " " proximal thick- 

 ness 028 



" " " " distal thickness. .017 



" " IV, length 016 



" " " " proximal width. .012 

 "' " proximal thick- 

 ness 022 



" " " " distal thickness. .015 



Second phalanx, digit II, length 026 



" " proximal width. .013 

 " " proximal thick- 

 ness 018 



" " " " distal thickness. .012 



" III, length 022 



" " proximal width. .018 

 " " proximal thick- 

 ness 024 



" " distal thickness. .015 



