EXPLANATION OF PLATE LIII. 



Fig. 1. Vertebral column, with pectoral tin, anil impression of opercula of Empo seniianceps, Cope, one- 

 half natural size ; an interruption between the dorsal and caudal series is not filled by I be 

 specimens : 1 a, obverse of the piece containing last dorsals, showing dermal bones. 

 2. Opercular, hyomandibular, quadrate, and angular bones of another specimen of Empo scmianceps 

 one-half natural size. 



Figs. 3-5. Parts of a single specimen of Empo nepccolica. 



Fig. 3. Tho mandibular ramus, natural size, from the iuuer side; 3 a, the same, from the outer side; 

 3 b, the angle and cotylus, from behind. 



4. Prernaxillo-maxillary boue of the same, natural size, viewed from below. ■ 



5. Cervical vertebrae and basioccipital boue of the same, from below, one-half natural size. 

 Figs. 6-9. Portions of a skeleton of Empo seniianceps, natural size. 



Fig. G. Dentary bone, from the outside. 



7. ? Pharyngeal boue, with dental alveoli. 



9. Dermal scuta. 

 Figs. 10-13. Empo merrillii, Cope, natural size. 



11-12. Premaxillary bone, from below. 

 Fig. 12. Proximal end. 



13. Pharyngeal bone, with alveoli. 

 Figs. 1-1-17. Empo contractu, Cope, natural size. 

 Fig. 14. Pharyngeal bone, with alveoli. 



15. Premaxillary and maxillary bones, from below. 



16. Proximal side of premaxillary, from the side. 



17. Dentary bone, from outer side. 



