PLATE XXVc. 



Figures all natural size. 



Fig. 1. — Diasacus navajoviun. Right mandibular ramus, external view ; o, from above. Page 345. 



Fig. 2. — Triisdon quiiirensis. Left mandibular ramus, with temporary fourth premolar, external view ; a, 

 the same, from above; b, the same, inner side, with the alveolar walls removed, displaying the per- 

 manent fourth premolar ; c, superior view of the permanent fourth premolar. Page 272. 



Figs. 3-4. — Conoryctes comma, typical specimen; fig. 3, left mandibular ramus, outer view; o, inner; b, 

 superior views; 4, left inferior canine tooth, external view; a, internal view. 



Figs. .VS. — Anigonchus sectorius ; p, maxillary bone, with three molars; a, from below; 6, mandibular 

 ramus of probably the same individual; a, from above; 7, mandibular ramus of a second individ- 

 ual ; 8, mandibular ramus of a third, with deeper ramus ; aa, from above. Page 413. 



