Cope.] ' ^'J^ . [May 3, 



men. The posttympanic process is distinct but short, presenting an ob- 

 tuse edge outwards, which is separated from the petrous by a groove. 

 The tympanic forms with the superficial layer of the petrous, a tube 

 wliich encloses the tympanum, and which separates widely the post- 

 tympanic and postglenoid processes. The postglenoid is confined to the 

 inner half of the posterior border of the glenoid cavity, and rises obliquely 

 inwards to its apex. The inner border is vertical. 



The palate is moderately flat, and is excavated behind as far as opposite 

 the middle of the penultimate molar. The diastema in front of the canine 

 is just half as long as that posterior to it. The width of the palate at the 

 antepenultimate premolar is just twice the width of that tooth. The 

 protuberance of the maxillary bone behind the last molar is about as long 

 as the fore and aft diameter of the last molar. The pterygoid process of 

 the palatine is not very long, and is slightly everted. Its superior border 

 is thickened and somewliat roughened, and descends posteriorly without 

 hamular process. The pterygoid wing of the sphenoid forms a prominent 

 ridge directed downwards and forwards, which encloses the large alisphen- 

 oid canal. The pterygoid bone is a delicate scale at the inner side of the 

 pterygoid ala, which extends as far back as the posterior alisphennid fora- 

 men. The basioccipital and basisphenoid are convex in cross-section. 

 The anterior part of the former is compressed, and the posterior part of the 

 latter presents two low truncate tuberosities, outwards, backwards and 

 downwards. The presphenoid region is contracted in the form of a part 

 cylinder, which is underroofed by the laminar posterior part of the vomer, 

 wliich extends nearly as far posteriorly at the sides as the posterior ali- 

 sphenoid foramen. 



Sutures. — Tlie sutures are distinct in this skull. That separating the 

 premaxillary and nasal bones is considerable, being about half as long as 

 the nasomaxillary suture posterior to it. The nasolachrymal suture is 

 about as long as the nasopremaxillary, and differs from it in being straight 

 instead of convex upwards. The nasal bones are widened behind so as 

 to be decurved laterally to the lachrymal. The posterior nasal sutures 

 are each convex backwards. The lambdoidal suture crosses the sagit- 

 tal crest in front of the inion and reaches the squamosal at the postparie- 

 tal foramen. The postfrontal is only in contact with the zygomatic pro- 

 cess of the squamosal, and at considerable distance posterior to the malar 

 above, but opposite the posterior inferior slip of the malar. The latter 

 bone extends as far forwards as the middle of the penultimate molar, and 

 rises upwards nearly to the middle of the orbit. The lachrymal bone is 

 a very large one ; it is a little higher than the facial part of the malar, and 

 extends a little further anteriorly. Its frontal suture is shorter than its 

 nasal, and extends nearly to the middle of the superior border of the orbit. 

 The premaxillo-maxillary suture passes into the incisive foramen at the 

 canine tootlu The maxillopalatine extends forwards as far as the front 

 of the first true molar, and posteriorly near to the last molar to the shallow 

 groove between the maxillary bone and the pterygoid process. 



