294 Annals of the Carnegie Museum. 



latter have the posteroulnar angle of the unciform greatly enlarged 

 in order to furnish support for the laterally expanded pyramidal above, 

 and the head of mc. IV below. 



The second metacarpal is not present in the type, but the small 

 excavation on the postero-radial angle of the third metacarpal together 

 with the articular facets on the trapezium, trapezoid, and the proximal 

 end of mc. Ill, make it quite evident that there was a short scale- 

 like mc. II in the manus of Stenomylus gracilis. On the postero-ulnar 

 angle of mc. IV are two small facets which indicate the presence of a 

 rudiment of mc. V. The unciform also has a very minute facet at the 

 base of the palmar hook which articulated with this scale-like meta- 

 carpal. The third and fourth metacarpals are coossified one half the 

 distance of their length, with the distal ends very slightly diverging. 

 The head of the canon-bone is very little expanded transversely. On 

 the dorsal face immediately below the articular facets there are prom- 

 inent tubercles for muscular attachment, which are quite similar to 

 those in Camelus bactrianus, though somewhat more prominent. The 

 anterior face of the shaft is very convex, the lateral faces less so, and 

 posteriorly the two bones meet to form a deep narrow groove, which 

 extends down the shaft two thirds of its length. Distally the diverging 

 shafts of the canon-bone show a more oblong outline in cross-section, 

 having the transverse diameter greater than the antero-posterior. The 

 distal trochlear of the individual bones (mc. Ill and IV) are very 

 little more expanded transversely than the shafts, and are in this 

 respect identical with Oxydactylus, while in the recent forms the 

 distal ends have a greater expansion laterally. The carina is damaged 

 in the type, but enough is present to indicate that it was of consider- 

 able development, but confined entirely to the plantar face of the 

 trochlea. All the phalanges of the manus are unfortunately not 

 present in the type specimen. 



Measurements. 



mm. 



Greatest length of humerus — 195 



Length of humerus from head to distal end 181 



Antero-posterior diameter of proximal end of humerus 3 52 



Greatest transverse diameter of head of humerus 37 



Transverse diameter of distal end of humerus 33 



8 The proximal end of the humerus has received some crushing laterally, which, in 

 part, may be due to the great diameter antero-posteriorly. 



