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lating with the pre-sphenoid above, the pterygoids and ali- 

 sphenoids behind, and with the maxillae in front. 

 (5) The jugals, a pair of laterally compressed bones. Each 

 jugal articulates with the squantiosal, and forms the greater 

 part of the zygomatic arch, and anteriorly fuses with the 

 zygomatic process of the maxilla. 

 (b.) The lower jaw. 



(a) The mandible, consisting of a pair of bones, each made up 



of a stout horizontal portion bearing the teeth, and a 

 thinner posterior portion, the angle, from which the ascend- 

 ing ramus takes rise and ends in the elongated condyle, 

 which articulates with the under surface of the zygomatic 

 process of the squamosal. 



(b) The hyoid bone, consisting of a median portion or body, 



and two pairs of cornua projecting backwards. 

 The Appendicular Skeleton. 

 The pectoral girdle. 



1. Remove the scapula from its muscular connections, and note — 



(a) Its triangular form, the apex directed downwards and forwards, and pro- 

 viding the glenoid cavity for the head of the humerus. 



(6) The spine, running along the outer surface, and ending in the acromion 

 process, which bears on its posterior surface the long metacromion 

 process. 



(c) The coracoid process, overhanging the glenoid cavity. 



2. The clavicle. Note its small size, its slender form, and its position in the 



ligament that runs from the scapula to the sternum. 

 The fore limb. 



Remove the muscles from the fore limb, and examine the following parts : — 



1. The humerus, an elongated bone, forming the skeleton of the upper arm, 



its head articulating with the glenoid cavity of the scapula, its trochlear 

 end with the supar-trochlear fossa in front, which communicates by the 

 supra-trochlear foramen, with the olecranon fossa behind. 



2. The bones of the fore-arm. 



(a) The radius, an elongated, slightly curved bone, lying in front of the ulna 

 at the elbow joint, but along its inner side at the wrist, articulating 

 at the elbow with the grooves of the trochlea of the humerus, and 

 with the anterior surface of the ulna, and at the wrist with the 

 carpal bones. 



(6) The ulna, an elongated bone articulating at the elbow with the humerus 

 by the sigmoid notch on its enlarged end, and with the radius by two 

 small surfaces, and at the wrist by its small end with the carpal bones. 

 Note, behind the elbow joint, the olecranon process of the ulna. 



3. The wrist, composed of two rows of carpal bones. 



(a) The proximal row, consisting of (1) the scaphoid (radiale) on the 



