EDENTATA OF THE SANTA CRUZ BEDS. 275 



. MEASUREMENTS. 



Ninth caudal, width over transverse pro- ? Sixteenth caudal, length of centrum. .0135 



cesses 0425 " " width of anterior 



? Eleventh caudal, length of centrum .. .0185 face oil 



" " width of anterior face .017 " " " over trans- 

 " over transverse verse pro- 

 processes 038 ccesses 016 



" height 023 ? Eighteenth caudal, length of centrum .0105 



? Thirteenth caudal, length of centrum .016 width of anterior 



width of anterior face 009 



face 014 " " " over trans- 



" over trans- verse pro- 

 verse pro- cesses 0125 



cesses 024 



Of the fore-limb only the radius is known ; it resembles that of Hapa- 

 lops, but is more slender in proportion to its length; the proximal facet for 

 the ulna is remarkably small and is confined to the postero-external aspect 

 of the head ; the surface for the humerus is transversely oval and has, in 

 addition to the usual concavity, a narrow plane facet on the inner side ; 

 the bicipital tubercle is very large ; the shaft is slender and antero-pos- 

 teriorly compressed. 



The pes is represented by the second and third digits. These are more 

 of the Analciiiiorplius than of the Hapalops type. Metatarsal II is more 

 elongate and slender than in the latter and the proximal end overlaps the 

 head of metatarsallll more extensively, but has no facet for the ectocunei- 

 form ; the distal trochlea is more asymmetrical than in Hapalops, the great 

 carina being displaced more toward the fibular border and projecting less 

 on the dorsal, more on the plantar side ; on the dorsal side of the shaft, 

 above the distal trochlea, is a large fossa not indicated in Hapalops. 

 Metatarsal III, though short and stout, is conspicuously longer and more 

 slender than in the last named genus, and the proportions of these two 

 metatarsals suggest that IV and V also were less abruptly different from 

 III than in the latter. 



In digit II the proximal phalanx is long and narrow, very thick planto- 

 dorsally ; in digit III this phalanx is of nearly the same length and, though 

 broader and far thicker than in II, is proportionately much less massive 

 than in Hapalops. The second phalanx is very long and quite slender and 

 in III is more elongate and less heavy than in the last named genus. The 

 unguals also differ in shape from those of the latter, being more decurved, 



