ANTROPOPS. 211 



GENUS HOMUNCULUS. 



Homunculus, Ameghino, Rev. Argent. Hist. Nat., i., pp. 290, 



384 (1891). 

 Ecphantodon^ Mercenat, Rev. Mus. La Plata, ii., p. 74, pi. ii. ; 



Zittel, Handb. Palseont., iv., p. 704 (1893). 



The dental formula of this genus is If, Cy, P|, M|. 

 The diastema, or break, in the dental series is very small ; the 

 incisors are chisel-shaped, the outer pair smaller than the inner 

 pair. The canines, which have a small basal cusp behind, are 

 only slightly prominent ; the pre-molars have one root, and one 

 low outer cusp, and two higher inner cusps. The molars are 

 quadrangular, with two pairs of cusps, each united obliquely by 

 a ridge ; the anterior molar is smaller than the two hinder. The 

 arm-bone {hiwierus)\i2i's> an ent-epi-condylar foramen. {Zittel.) 

 The front surface of the line of union of the two halves of the 

 lower jaw is vertical. The terminal joints of the digits have 

 nails. The thumb and the great-toe are opposable. Homun- 

 CULUS PATAGONicus, Amcghino ( = Ecphantodoti ceboides^ Mer- 

 cenat), the only known species, is found in the Upper Eocene 

 or Oligocene of Santa Cruz, Patagonia. 



GENUS ANTHROPOPS. 



Anthropops^ Ameghino, Rev. Arg. Nat. Hist., i., p. 387 (1891) ; 

 Zittel, Handb. Palaeont., iv., p. 704 (1893). 



This genus is known from only a fragment of a lower jaw 

 containing four small incisors, two strong canines, and anterior 

 and median pre-molars, both one-rooted. One species, Anthro- 

 pops PERFECTUS, Ameghino, from the older Tertiary (Upper 

 Eocene or Oligocene) beds of Santa Cruz, Patagonia, is known. 



Two genera, Homocentrus (H. argentinus, Amegh.) and 



p 2 



