16 



ELEMENTARY PHYSIOLOGY 



the breast-bone or sternum (see Lesson IV.). In the 

 girdle which supports the shoulder, two bones are always 

 distinguishable as the scapula and the clavicle. The 

 pelvis, to which the legs are attached, consists of two 

 separate bones called the ossa innominata in the adult ; 

 but each os innoininatum is separal)le into three (called 

 pubis, ischium, and ilium^ in the young. 



Fin. 3.— SinR View of the SKfix. 



/, frontal bone ; -p, parietal ; o, occipital ; (i, wing of sphenoid ; «, flat 

 part of temporal ; c, m, st, other jiarts of temporal ; (in, opening of ear 

 or external auditory canal ; z, process of temporal passing to j, the cheek 

 bone ; mx, the upper jaw bone ; n, nasal bone ; f, lacrymal ; pt, part of 

 jphenoid. The lower jaw bone is drawn downwards ; r//, its process 

 which articulates with the temporal ; cr, its process to which muscles of 

 mastication are attached ; lli, tij, hyoid bone. 



There are thirty bones in each of the arms, and the 

 same number in each of the legs, counting the patella, 

 or knee-cap. 



