154 



THE DESEADO FORMATION OF PATAGONIA 



found no specimens of this species. The following are 

 the measurements of the type according to Ameghino. 



Lower dentition, molar I, length 

 Lower dentition, molar 2, length 



31 mm., width 16 mm. 

 42 mm., width 21 mm, 



Parastrapotherium martiale Ameghino: 



P. martiale Amegh., 1901, Bol. Acad. Nac. Cordoba, t. 16, p. 402. 

 P. superablie Amegh., 1901, Bol. Acad. Nac. Cordoba, t. 16, p. 402. 



The species seems to have been founded on abundant 

 material, representing an animal of larger size than P. 



holmbergi, which is dis- 

 tinguished by the 

 greater width of the 

 crowns of the incisors, 

 by straight canines 

 diverging but little, by 

 a strong cingulum on 

 the outer side of the 

 lower molars and the 

 inner side of the upper 

 molars, and by the 

 narrow symphysis of 

 the lower jaws. P. 

 superabile was distinguished by a difference in the arrange- 

 ment of the roots of upper pm. 4, but as the pattern of the 

 crown is the same, as is also the size, I feel that this differ- 

 ence is simply an individual variation. The following 

 measurements are given by Ameghino: 



Fig. 1 08. Upper molar i of the left side 

 after Ameghino. 



-natural size, 



Upper dentition, length from pm. 3 to m. 3 



Uppt-r dentition, premolar 4, length 



Upper dentition, premolar 4, width 



Upper dentition, molar 2, length 



Upper dentition, molar 2, width 



Lower dentition, length from inc. I to m. 3 



240 mm . 

 30 mm. 

 43 mm, 



82 mm. 



83 mm. 

 550 mm. 



