138 iMUSCULAR SYSTEM. 



Attachment. — Superiorly, to the whole of the posterior costa 

 of the scapula : inferiorly, to the superior and posterior parts of 

 the olecranon, and postero-internal part of the brachial faschia, 

 immediately below that process. 



Direction. — Downwards and backwards j converging towards 

 the olecranon. 



Relations. — Externally, with the faschia and skin, teres minor, 

 and postea spinatus ; internally, with the pectorales, magnus et 

 parvus, and the teres major: anteriorly and inferiorly, with the 

 caput medium and humerus ; superiorly and posteriorly with the 

 scapula, and the faschia and skin. 



Structure. — Even this large head itself may be dissected into 

 two portions (to which Bourgelat and Girard have given dis- 

 tinct names) : one is long, thin, and flattened, and aponeurotic 

 at its attachments, but fleshy in its middle, and lies along the 

 postero-internal border of the other, which constitutes the chief 

 bulk of the entire muscle. 



The scapular attachments are fleshy upon the outer side, ten- 

 dinous upon the inner. The surfaces are in places aponeurotic. 

 The belly or middle part is fleshy, with the exception of a thick 

 tendinous intersection, which, together with the aponeurosis, 

 ends in a broad, thick, flattened tendon, that is implanted into 

 the olecranon. 



CAPUT MEDIUM, — Humero-ohcrauius Externus. 



Situation. — Infero-external part of the shoulder. 



Form. — Oblong : flattened. 



Attachment. — Superiorly, to the outer side of the neck, and 

 to the ridge extending from the outer tubercle upon the body 

 of the humerus : inferiorly, to the postero-oute'r parts of the 

 olecranon. 



Direction. — From above, downwards ; and from before back- 

 wards. 



Relations. — Externally, with the postea-spinatus, teres minor, 

 and faschia and skin ; internaHy, with the humeralis externus 

 and outer condyle of the humerus : anteriorly, with the faschia 

 and skin ; posteriorly, with the caput magnum. 



Structure. — Superior attachment, both fleshy and tendinous. 

 Middle part, fleshy. Inferior attachment, fleshy and tendinous, 

 and inseparably united in one common tendon with the caput 

 magnum. 



CAPUT PA Rv u M. — Ilumcro-olecrcinius Internus. 



Situation. — Infero-internal part of the shoulder. 



Foini.— Long and slender; and flattened. 



