1884.J DDD [Cope. 



V-shaped, and is in line with the posterior edge of the maxillary bone. The 

 latter projects beyond the last molar tooth as far as the anteroposterior 

 diameter of the latter. It has no projection in the G. simus. There is no 

 notch between the maxillary bone and the processes pyramidalis of the 

 palatine. The palate is of nearly equal width from the last molar to the 

 third premolar ; its roof is gently concave posteriorly ; nearly flat anteri- 

 orly. 



The premaxillary bone is a narrow strip which rises nearly vertical- 

 ly from its short alveolar border, and is curved outwards above in 

 agreement with the expansion of the anterior edge of the maxillary, to 

 which it is united by simple suture. The nasal bones are of remarkable 

 form. Together they enter the anterior part of the frontals in a V-shape, 

 and extend forwards in a narrow shaft. Opposite the anterior borders of 

 the orbits the shaft begins to widen gradually, and the surface to flatten, 

 until they reach the posterior angle of the ascending part of the maxillary. 

 Each one then expands outwards, terminating in a semi-disc which fits 

 the concavity of the superior edge of the maxillary above mentioned. 

 The entire shape of the nasal bones is that of a spade with a triangular apex 

 to the handle, and the short blade at the opposite (anterior) extremity. 

 The frontal bone is V-shaped, the angle posteriorly directed, and engaged 

 between the parietal bones, and each branch terminating above each orbit. 

 Narrow prolongations extend anterior and posterior to the orbit, joining the 

 lachrymal and malar bones respectively. Its median suture is, like that of 

 the nasal bones, well defined. The alisphenoid and parietal have extensive 

 •connection. The parietosquamosal suture is horizontal in front ; it then 

 gradually rises. It is not associated with a ridge as in some other species. 

 The occipital forms the posterior five millimeters of the sagittal crest. 



The nasal opening is subtriangular, with the base above, and is directed 

 anteriorly. The facial vacuities are enormous, and excavate the frontals 

 to a point which make the anterior third of the orbit's diameter. They are 

 only separated on the median line by the very narrow isthmus of the 

 nasal bones. The infraorbital foramen is above the anterior part of the 

 fourth surperior true molar. The frontal foramina are small, and are not 

 symmetrical. That of the left side is half-way between the median suture 

 and the superciliary border ; the other is nearer the superciliary border. 

 No supraglenoid foramen. Postsquamosal present ; that part of the 

 cranial walls is injured. The anteroposterior diameter of the orbit ex- 

 ceeds the vertical. The auricular meatus is the largest known in the 

 family, and it has a prominent border and regularly oval outline. Its 

 long diameter rises posteriorly from the horizontal. It is more lateral- 

 ly and less posteriorly directed than on the typical and only skull of 

 G. simus. The foramen magnum has an openly angulate superior bor- 

 der. Jugular, condyloid., and carotid foramina not obvious, owing to the 

 close contact of the otic bulla with surrounding bones. Foramen ovale 

 larger than the F. lacerum anterius, and external to it in position. F. ro- 

 tundum still larger, inferior in position, bounded on the external side by a 



