PHARSOPHORUS 215 
so I have reproduced Ameghino’s figure and give his 
measurements. 
Lower dentition, length incisor I to molar 3 114 mm. 
Lower dentition, length premolar 1 to molar 3 go mm, 
Lower dentition, height of mandible under pm. 4. 38 mm. 
Pharsophorus tenax Ameghino 
P. tenax Amegh., 1897, Bol. Inst. Geog. Argen., t. 18, p. 504. 
The species was based on a fourth premolar which was 
10 mm. long as compared with 13 mm. in P. lacerans. We 
found on the Chico del 
Chubut, west of Puerto 
Visser, both an upper and 
lower jaw belonging to this 
species, which give us the 
knowledge of the upper den- 
tition for the genus. The 
species is distinguished by 
the smaller size, relatively 
heavy jaws, and plump 
teeth, indicating a heavier 
mv. m3. 
Fig. 140. Left upper jaw—t1/2 natural size; A, 
molars 3 and 4 from above; 4, molars from ex- 
ternal side. 
built animal than P. lacerans. 
The following measurements distinguish the species. 
Fig. 141. Right mandible—1/2 natural size. 
SPECIMEN 3192 
Upper dentition, length premolar 1 to molar 3 76 mm. 
Upper dentition, premolar 3, length 
Upper dentition, molar 1, length 
Upper dentition, molar 2, length 
Upper dentition, molar 3, length 
10.5 mm., width 6 mm. 
11.5 mm., width 8.5 mm. 
é 12 mm. width g mm. 
.55mm., width 12 mm. 
