16 



is quite concave. The sustentacula! facet is continuous with it, and forms an oval in 

 the longitudinal axis of the astragalus. The cruscular facet is transverse and concave. 

 The tuber is not very robust and is moderately oblique. 



Measurements. 



I. Calcaneum. 



Mm. 



Total length 123 



" of tuber SO 



Width of tuber at base 43 



" at sustentaculum 84 



(■Vertical 26 



Diameters of cuboid facet ■] 



(. Transverse 46 



II. Astragalus. 



( of trochlea 67 



Width 1 



(. below trochlea 75 



I inner side 60 



Length < 



I outer " 55 



Width of distal facets 70 



" " navicular facet 42 



" "cuboid " 29 



Vertical diameter of navicular facet, at middle • 40 



" " ofcuboid " " 25 



The scaphoid appropriate to this species has, like the others, the facet for the magnum 

 at the extremity of a step-like projection. The trapezium facet is but little smaller than 

 that for the trapezoides. Both are subtriangular, while that for the magnum is antero- 

 posteriorly oval, with straight internal and posterior borders, which unite at an angle 

 Area about equal to that of the trapezoid facet. The bone differs from the large scaphoid 

 before mentioned, in having the lower facet abbreviated posteriorly by a fossa, which is 

 small and upward-looking in the latter. 



The magnum referred to the M. angusligenis has the anterior face wider than deep. 

 The corresponding bone of the large species differs from it in having the metacarpal facet 

 relatively a little wider, and in having at the lateral posterior edge of that facet a narrow 

 anteroposterior oblique facet, apparently for an internal facet of the proximal end of the 

 fourth metacarpal. 



Measurements of Scaphoidcs and Magnum, in Mm. 



I. SCAPHOIDES. 



M. (?) americanus. M. angusligenis. 

 f Anteroposterior 90 75 



f at trapezoides 24 23 



Diameters \ Vertical i 



( at magnum 50 45 



Transverse at middle 61 50 



Width of facet for magnum (transverse) 39 27 



" " trapezoides (anteroposterior) 19 27 



" '' " trapezium ( " ) 22 27 



