364 



MR. C. FORSTER -COOPER ON 



There is yet another specimen of a lower jaw with a much- 

 worn first molar and roots of the hist premolar and second and 

 third molars. The first molnr is 22 mm. long and about 12 mm. 

 broad, and is therefore larger than the other specimens. The 

 lower border of the jaw is extremely straight, as in Phyllotillon 

 naricus. In size it seems to correspond witli Pilgrim's unnamed 

 fragment. Whether it represents a sexual difference from 

 Schizotherimn jnlyrimi or yet a third species remains unsolved. 



Text-figure 5. 



? Metacarpal or metatarsal of a Clialicotlieroid. Nat. size. 



Until the anatomy of these animals, and indeed of all Chalico- 

 theres with the exception of M or opus, is better known, it is 

 impossible to feel sure of their generic position. A good deal 

 of interest lies in the condition of the feet and the gradual loss of 

 the first and fifth toes. According to Holland and Peterson *, 

 both should be present in the foi-e foot of the Scliizotheriince. In 

 the present collection are seveial phalanges and one bone which 

 ma}^ be a lateral podial (text-fig. 5) ; it is just possible that it 

 may lepiesent a. fifth metacai-pal or tarsal. Of the phalanges 

 three out of six show the co-ossification of the proximal and 

 median (text-fig. 6), which was evidently a common feature, as 

 Holland and Peterson describe it in Moroims. The free proximal 

 phalanges all show strongly-marked tubercles on the posterior 

 faces (text-fig. 7) for the flexor attachments. Some of the 

 fused bones show this feature, but to a less degree. They are 

 not to be found in corresponding bones of Macrotherium or 



* Loc. cit. p. 201, 



