374 PATAGONIAN EXPEDITIONS I PAL/EONTOLOGY. 



a bluntly rounded point, with a prominent ridge external and anterior to 

 it. The forearm bones of Notoryctes have a curious resemblance to those 

 of the two insectivorous genera ; the radius is shorter, but its transversely 

 oval head is more like that of Necrolestes; the olecranon of the ulna is 

 much more slender and more decidedly curved than in the fossil, curving 

 more posteriorly and less internally. 



As is well known, Chrysochloris possesses a third fore-arm bone, which 

 is as long as the radius and which runs from the palmar face of the carpus 

 to the elbow joint, where it has a ligamentous connection with the entepi- 

 condyle of the humerus. Flower regards this as apparently " an ossifica- 

 tion in one of the flexor tendons " ('85, p. 275). The same structure appears 

 to have been repeated in Necrolestes, though only the distal portion of it 

 is ossified. 



Of the carpus are preserved in one individual the scaphoid, lunar, trape- 

 zoid and magnum, and in connection with the latter the third metacarpal. 

 A second specimen contains the pyramidal and unciform. Though much 

 less reduced and specialized, the resemblance of these carpal bones to those 

 of Chrysochloris is unmistakable. The scaphoid is a very large bone pro- 

 portionately ; it is much like that of the African genus, but relatively larger ; 

 the radial facet takes up but little of the proximal end of the bone, where 

 it forms a small convex prominence. The palmar side of the scaphoid 

 bears an articular surface, though it is not apparent what purpose this facet 

 may have served. The distal end carries three facets, for the trapezium, 

 trapezoid and magnum respectively, all of which are concave in shape, and 

 that for the trapezium is exceedingly small ; the facet for the magnum is 

 small but distinct. 



The lunar is much smaller than the scaphoid, though, like the latter, 

 relatively larger than in Chrysochloris. It has a broad, convex proximal 

 facet for the radius, which descends well upon the anterior face of the 

 bone. The distal articulation appears to be entirely with the magnum, 

 and if there was any contact with the unciform, it must have been a very 

 limited one. 



The pyramidal is likewise proportionately larger than in Chrysochloris 

 and covers the whole distal end of the ulna ; it is short proximo-distally 

 and rather broad. 



The trapezium is not preserved in any of the specimens, but its presence 

 may be inferred from the facet on the scaphoid. The trapezoid is exceed- 



