156 THE SKULL. [CHAP. 



joins the periotic, forming the floor of the tympanic cavity 

 without being inflated into an auditory bulla. Its under 

 surface is produced into a rough ridge, to the inner side of 

 which the large carotid canal perforates the base of the 

 periotic, being directed obliquely forwards and inwards. 

 In adult skulls the stylohyal often becomes ankylosed with 

 the tympanic and periotic, constituting the " styloid process 

 of the temporal bone." 



In examining the external aspect of the skull, the large 

 smooth subglobular or oval brain-case, constituting by far the 

 larger part of the whole cranium, is strikingly different from 

 that of the Dog. The occipital surface, instead of being 

 vertical, is nearly horizontal. The condyles, instead of 

 being at the hindermost part of the skull, are not far from 

 the middle of the base. The paroccipital processes of the 

 exoccipitals are represented by mere rudiments, the so-called 

 "jugular eminences"; on the other hand as before men- 

 tioned, the mastoid processes, almost obsolete in the Dog, 

 are very greatly developed. The occipital crest is repre- 

 sented by a slightly raised and roughened line, the " superior 

 curved line," and the sagittal crest is absent. 



The sutures connecting the bones of the upper surface 

 of the cranium are remarkable for their wavy or indented 

 character, processes from one bone interlocking with those 

 from the other in a most complex manner, at least on the 

 external surface, for seen from within they appear com- 

 paratively straight and simple. There are very often 

 irregular ossifications, separated from the contiguous bones, 

 lying among the indentations of the occipito-parietal suture, 

 called "Wormian bones." 1 The temporal fossa? are but 



1 In works on human anatomy, the occipito-parietal suture is com- 

 monly called " lambdoid ; " the interparietal, "sagittal;" and the 

 front j- parietal, " coronal." 



