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tubercle of the humerus. The subscapularis arises from the internal 

 siirface of the scapula ; it passes upwards, and is inserted into the 

 posterior part of the middle tubercle of the hitmei-us. The teres minor 

 arises from the whole width of the posterior surface between the 

 glenoid cavity and the end of the upper third of the scapula ; it passes 

 in the groove, and is inserted into the inferior part of the large tu- 

 bercle of the humerus. Of the triceps extensor cubiti the long head 

 arises immediately above the origin of the teres minor, and passing 

 down on the external side of the humerus, it is joined by the second 

 head, arising from the internal part of the \avge Jbramen cacum of 

 the humerus ; these two unite about the middle of the arm, and are 

 joined by the third head, which arises from the two inferior thirds of 

 the posterior edge of the humerus till within 8 lines of the joint : it 

 is no\v attached to the sesamoid bones of the elbow-joint, and to 

 th&Jbssa on the inferior parts of the posterior surface of the os 

 humeri. 



" The anconeus arises from this musele, and from the part of the 

 bone below the origin of the third head, and is attached to the sesa- 

 moid bones anterior to the triceps extensor cubiti. Instead of a biceps 

 and brachialis internus, there is a triceps Jlexor cubiti, the long head 

 of which arises, tendinous, from the antero-interior part of the su- 

 perior angle of the Jhrculum, and, passing over the joint, is joined, 

 at the union of the upper with the middle third of the humerus, by 

 the fibres of the middle head, vvhich arises fleshy from thejlirculum 

 immediately behind the Jbramen formed by the union of the three 

 bones of the shoulder passing on to join the long head ; at the head 

 of the humerus it is joined by the short head which arises from the 

 anterior part of the Jbramen ccecum ; vvhen it reaches the superior 

 part of the middle third of the humerus, it joins the other tendons, 

 and then forms an aponeurosis over the elbow-joint, and is attached 

 to the middle part of the radius. A musele arises from the anterior 

 superior edge immediately below the arterial groove on the lower 

 part of the humerus ; it passes directly downwards and is inserted 

 into the radial extremity of the metacarpal bone and into the edge 

 of the carpal ligament. The^e^or communis arises from the inter- 

 nal side of the humerus, from the ligament of the elbow-joint, and 

 from the superior part of the radius and tdna ; it divides into two 

 tendons, which go down in the interosseal space, passing under the 

 ligamentum carpi annulare posterius, and are attached to the first and 

 each succee(\.ing phalanx of the two fingers about 5 lines belovv their 

 articulations. The extensor communis has the šame situation and 

 number of attachments on the external or dorsal side of the humerus. 

 There is apronator quadratus arising as is usual in this class. There 

 is also a musele which arises from the anterior part of the radius at 

 its distal extremity, and is inserted into the projection of bone 

 formed by the phalanx of the second finger, and also, by a slip, into 

 the internal part of the first phalanx of the first digit. 



" The museles serving for the motion of the inferior extremity 

 inay be described as follows. 



