394 THE PUERCO EPOCH. 



M. 



length of base Pm. iii 013 



Width of base Pm. iii OCjo 



Length of base Pm. iv 013 



Width of base Pm. iv 010 



Diameters M. ; $ a^toroposterior Oil 



I transverse wv 



Diameters M. iii 5 ='"*^'^''1'°*"'"°' °^'^ 



■ < auter 

 c trans 



ransverse 008 



Depth ramus at Pm. ii 0225 



Depth ramus at M. iii 0296 



Depth of ramus posterior to M. iii 052 



Length of bases of two superior incisors 012 



Diameter of base of crown superior canine 007 



Length of superior true molars 028 



_. . , . _ , .(anteroposterior 0096 



Diameters of superior molar i < ■ 



( transverse 01 1 



_.. . - , ...< anteroposterior 009 



Diameters of superior molar in ^ ^^ 



( transverse 010 



No. 2. 



Length superior premolar series 049 



_. . T. .< anteroposterior 009 



Diameters Pm. li '^ „.-. 



( transverse 009o 



_. . „ ...(anteroposterior 013 



Diameters Pm. in < ' 



< transverse 014 



Elevation of occipital crest laterally above foramen maguum 044 



Anteroposterior diameter of paroccipito-posttympanio process 017 



Anteroposterior diameter of meatus auditorius 009 



Anteroposterior diameter of glenoid cavity at postglenoid process 015 



The cervical vertebrae, as already remarked, are about as long (or short) 

 as those of the species of Ekphas, but are more depressed. The axis is less 

 shortened, as its centrum has much the proportions of that of Bhinocerus. 

 The atlas is shorter than in the latter genus. Unlike most genera of mam- 

 malia, in PerijHychus, the vertebrarterial canal pierces the base of the ver- 

 tically compressed diaparapophysis precisely as in Elephas. Its position is 

 a little above opposite the fundus of the odontoid foramen, and nearly in 

 the position it occupies in the Eleplias africanus. The condylar cotyli have 

 full convex borders, and their articular surface is without constriction. 

 Axial facets flat and subround. The axis is preserved in Nos. 1 and 3. The 

 atlantal facets are distinct from each other, are subround, and slope at an 

 angle of 45° with the middle line. Vertebrarterial canal complete (neural 

 arch and extremity of transverse process lost). The floor of the neural 

 canal is wide and flat, and is pierced by two small fomraina posterior to the 

 middle. Inferior face flat, with a faint trace of angular keel. The centra 



