50 THE TONER LECTURES. 



7. The Anterior Part of the Lateral Mass of the Ethmoid Bone. 



This region, as a rule, lias a narrow border. The superior 

 border of the middle turbinal and the base of the uncinate process 

 here unite. Occasionally, as is seen in a Peruvian skull,^ the three 

 structures are separated by a large globose surface, which forms the 

 boundary of the most advanced of the ethmoid cells. 



The Uncinate Process. — The uncinate process is flat and usually 

 lies on the plane of the outer wall of the nose. In a low type 

 of skull (this is well exemplified in a Hottentot,^ in which it is 

 firmly united to the inferior turbinal) the process may be found 

 lying transverse to the long diameter of the nasal chamber, and of 

 such dimensions as almost entirely to conceal the large middle tur- 

 binal. This disposition is seen in the left side of a skull of a 

 Negro,^ and in a second from Santa Barbara, Cal. In two Peru- 

 vian* skulls the uncinate process on the left side is united to the 

 ethmoid cells. 



The degree to which the uucinate process extends in an antero- 

 posterior direction is subject to considerable variation. It may be 

 in contact anteriorly with the inferior turbinal, so that an opening 

 on the lateral wall of the chamber alone exists between the pedicle 

 of the uncinate and the ascending process of the superior maxilla. 

 It may be entirely free from the inferior turbinal at this section of 

 the chamber, so in place of a foramen a long interval is found between 

 its antero-inferior limit and the maxilla and the inferior turbinal. 

 The extent to which the opening into the maxillary sinus is nai'- 

 rowed is also subject to variation. The opening appsars to be the 

 smallest in the prognathic and the largest in the orthognathic form 



of crania. 



THE VERTEX. 



The sconce or crown constitutes in thelanguage of craniology the 

 vertex. The main parts comprising it are so easily determined by 



iNo. 1432. 2 No. 1107. 



3 No. 964. ■'No. 1705, 1432. 



