THE CRANIUM. 11 



Superior Face. — From the vertex of the superior ridge of the occipital superior 



Face. 



bone to the anterior edge of the nasal bones, there is an obliquity forwards 

 (Large Plate, and Plates I. and XVI.). From the latter to the anterior ter- 

 mination of the premaxillaries, the inclination is more considerable, being 

 about fifty degrees. The cranium between the temporal fossae is very much 

 compressed. The face below the nasal opening is nearly double the width of 

 the cranium. At the posterior termination of the vertex, we see the superior 

 occipital ridge, which is very rough for the attachment of the cervical 

 muscles. In front of this ridge is the smooth superior parietal surface, 

 deeply indented laterally by the edges of the temporal fossa?. The parieto- 

 frontal surface is bounded anteriorly by the bifurcated extremities of the 

 ossa nasi, and a ridge forming the posterior boundary of the nasal fossa. 



Below the nasal bones we perceive the nasal orifice, which is oblong in 

 the transverse direction; being twelve inches transversely, and six from 

 above downwards in the median line. The circumference of this orifice is 

 of an oval form, flattened below. The nasal aperture leads into a fossa, 

 which is twenty-four inches in depth from the edge of the ossa nasi to the 

 posterior inferior edge of- the pterygoid process of the sphenoid bone. On 

 the superior face of the nasal fossa interiorly, we find two obliquely rounded 

 apertures, each about two inches in their longest diameter, leading to the 

 frontal sinuses. Below these is seen the nasal plate of the os ethmoides, 

 which, united with the vomer, forms a partition between the right and 

 left cavities of the nostrils. These passages are five fingers wide from 

 above downwards, and four from side to side, or across. 



At the anterior part of the nasal orifice is a groove eight inches long, 

 which, beginning at the vomer, terminates below the cavity of the nostrils 

 in a free edge. Here the two premaxillary bones, uniting at the median 



