PLATE LVI. 



Jaws of Perissodactyla. Natural size. 



Fig. 1.— Part of skull of Systemodon tapirinus Cope, obliquely distorted by pressure, with mandibular 



ramus not distorted, from right side; a, maxill.ary bone, from below; b, niaudible, from above. 



Page 019. 

 Fig. 2.— Syuiphysis and part of ramus of mandible of a second individual of Systemodon tapirinus, left 



side ; a, from above. The posterior inferior molar on anotlicr part of the ramus is preserved, but 



not figured. Page 619. 

 Fig, 3. — Systetiwrloii srmihiaiis. Superior molars ami canine, from l)elow ; molars worn. Page (522. 

 Fig. 4. — Supposed mandililo of Systemodon scmihians, from left side ; a, from above. Page 662. 

 Fig. 5. — Systemodon etsagicua. Part of mandibular rauuis, external view ; a, from above. 

 Fig. 6. — Heptodon posticus. Left mandibular ramus, internal side; a, from above. Page 654. 



