CLASSIFICATION, AND PHYLOGENT OF THE DINOENITHID.^. 407 



9. W'idt/t of cranium at preorlital processes : lengtli of a straiglit line joining the 

 posterior borders of the lacrymals. 



10. Distance between temporal ridges : length of the shortest straight line joining 

 the right and left temporal ridges. 



11. Height of cranium : length of a perpendicular from the highest part of the 



cranial roof to the basitemporal platform. 



12. Width oftympa7iic cavity: length of the longest horizontal straight line joining 

 the posterior temporal ridge and the edge of the paroccipital process. 



13. Width of temporal fossa : length of the longest horizontal straight line joining 

 the anterior and posterior limbs of the temporal ridge, above the junction with 

 the latter of the posterior temporal ridge. 



14. Width of orbit : length of the longest horizontal straight line joining the posterior 

 border of the lacrymul and the anterior border of the postorbital process. 



15. Bistatice bettveen opdic foramina : length of a straight line joining the lower 

 borders of the foramina. 



16. Greatest length of premaxilla : from apex of body in a straight line to posterior 

 end of nasal process. 



17. Length of premaxilla to end of maxillary process : from apex of body in a straight 



line. 



18. Length of body of premaxilla : length of a straight line between apex and 



posterior border of prenarial septum. 



19. Width of body of premaxilla : length of a straight line between the right and 

 left alveolar borders at the level of the posterior edge of the prenarial 

 septum. 



20. Length of maxillo-jngal arch : the greatest length in a straight line. 



21. Length of vomer: the greatest length in a straight line. 



22. Length of palatine : the greatest length in a straight line. 



23. Length of pterygoid : the greatest length in a straight line. 



24. Length of quadrate -. length of a straight line from the articular surface of the 

 head to the most prominent part of the internal condyle. 



25. Length of mandibular ramus : from middle of anterior border of symphysis to 



extremity of posterior angular process. 



26. Greatest height of mandible : length of a perpendicular from the coronoid process 

 to the ventral border. 



27. Least height of mandible : a similar measurement of the anterior part of the 



ramus a short distance posterior to the symphysis. 



28. Ljcngth of mandibnlar symphysis : length of a straight line passing from the 



middle of the anterior to the middle of the posterior border of the symphysis. 



29. Width of mandibular sym2)hy sis: length of a straight line between the right and 

 left alveolar borders at the level of the posterior edge of the symphysis. 



3m2 



