208 



THE DESEADO FORMATION OF PATAGONIA 



Octodontotherium grandis Ameghino 



O. grandis Amegh., 1895, Bol. Inst. Geog. Argen., t. 15, p. 656. 

 O. grandis Amegh., 1897, Bol. Inst. Geog. Argen., t. 18, p. 505. 



In addition to the above, Ameghino simply gives the 

 following measurements: 



First upper tooth, ant. -post. diam. 20 mm., trans, diam. 13 mm., height 80 mm. 

 First lower tooth, ant. -post. diam. 21 mm., trans, diam. 16 mm., height 80 mm. 

 Last lower tooth, ant. -post. diam. 28 mm., trans, diam. of ant. lobe 18 mm. 

 Last lower tooth, trans, diam. of post, lobe 16 mm., median diam. 7 mm. 



Fig. 136. A, lower molar, side view — natural size; B, 

 lower molar, cross section — natural size; C, upper molar, 

 cross section — natural size, after Ameghino. 



Octodontotherium crassidens Ameghino 



O. crassidens Amegh., 1897, Bol. Inst. Geog. Argen., t. 18, p. 505. 



This second species is based on isolated teeth of larger 

 size than the preceding, with measurements as follows: 



Upper molar, ant. -post. diam. 26 mm., trans, diam. 18 mm. 

 Lower molar, ant. -post, diam., 26 mm., trans, diam. of ant. lobe 21 mm., trans, 

 diam. of post, lobe 16 mm. 



