PARASTRAPOTHERR'M 149 



of the pillar in the lower molars, which is a character 

 due to youth; so I have considered it a synonym of P. 

 holmbergi. P. ephebicum is a much smaller and distinct 

 species, with which I should associate the single upper 

 molar to which the name P. lemoinei has been given. 

 P. martiale is a large species, distinguished by the strung 

 development of the cingulum on the internal side of the 

 upper molars, and on the inner side of the lower molars; 

 and by lower premolar 3 being well developed with two 

 roots. P. superabile is of the same size as the foregoing, 

 but has the cingulum on upper premolar 4 (the only tooth 

 known) less developed. I should therefore consider it a 

 synonym of P. martiale. P. insuperabile is the largest 

 species, and is distinguished by the excessive development 

 of the cingulum. Liarthrus is founded on an upper pm. 4 

 with a part of pm. 3, but, as far as I can see, does not differ 

 in character or size from P. holmbergi. Traspoatherium 

 is based on upper premolars which are distinguished by 

 the roots being fused from side to side. I think it is an 

 age character and for the present would consider it the 

 same as P. holmbergi, probably the tooth being pm. 3. 



Parastrapotherium holmbergi Ameghino 



P. holmbergi Amegh., 1895, Bol. Inst. Geog. Argen., t. 15, p. 636. 

 P. holmbergi Amegh., 1897, Bol. Inst. Geog. Argen., t. 18, p. 449. 

 P. troussarti Amegh., 1895, Bol. Inst. Geog. Argen., t. 15, p. 638. 

 P. troussarti Amegh., 1897, Bol. Inst. Geog. Argen., t. 18, p. 449. 

 Liarthrus copei Amegh., 1895, Bol. Inst. Geog. Argen., t. 15, p. 641. 

 Liarthrus copei Amegh., 1897, Bol. Inst. Geog. Argen., t. 18, p. 451. 

 Traspoatherium convexidens Amegh., 1895, Bol. Inst. Geog. Argen., t. i^, p. 



641. 

 Traspoatherium convexidens Amegh., 1897, Bol. Inst. Geog. Argen., t. 18, p. 



450. 

 Parastrapotherium holmbergi Tournier, 1905, Bui. Soc. Geol. France, >er. 4, 



t- 5, p. 305. 

 Astrapotherium holmbergi Gaudry, 1906, Anal. Palaeontologie, t. 1. p. 5. 



To this, the type species, I have assigned all the material 

 we found on the Chico del Chubut, west of Puerto Yisser, 



