210 DETAILED SYNTHESIS. 



sometimes all are, leaving the cranium one bone. For de- 

 scription of each bone, see Plates and their descriptions. 



290. THE CRANIUM HAS NO OPENINGS above ; those 

 it has are all below, and in a very small space, for the 

 transmission of Nerves and Blood-tubes. (See Plate 

 11, Figs. 5,6.) 



291. THE SPHENOID, ETHMOID, AND (in males) 

 FRONTAL BONES have cavities in them called cells (see 

 Fig. 148, and Fig. 4, PI. 11), the precise use of which is 

 not known, except it may be to enlarge the bones with- 

 out increasing their substance. 



292. THE FACIAL BONES ARE very irregularly shaped, 

 and attached to the lower front portion of the Cranium, 

 forming various cavities for the lodgment of the organs 

 of sense, and those required in mastication. 



293. THE FACIAL BONES CAN BE BEST DESCRIBED in 

 connection with the organs for which they are construct- 

 ed, except as they are described in connection with the 

 Plates. 



294. IT is TO BE OBSERVED IN PARTICULAR, by means 

 of the preceding cut, that the lower portion of (7) the 

 upper jaw-bone, that extends up by the side of the nos- 

 trils hangs down some distance below the bottom of the 

 Cranium, and of course the cavity of the mouth is still 

 lower. 



295. Hence, if the skull is placed upon the spinal 

 column, the eye could look through the cavity of the 

 nose against the upper part of the column, or if the fin- 

 gers should be passed up behind the facium and in front 

 of the spinal column, and turned forward, they would en- 

 ter tiie passages for the nose. The same IDEA is ILLUS- 

 TRATED BY FIG. 160. 



296. THE OBJECT OP TAKING PARTICULAR NOTICE OP 

 THE NASAL BONES, and the manner in which they hang 

 from the Cranium, is to understand the relation of the 



290. Whre ? 291. What have ? 292. What said ? 293. How ? 

 294 What ? 295. What ? 296. What ? 



