_Teres Major_ (Grosser runder Muskel oder kleiner Rückwärtszieher des Oberarmbein, Zweiter teres major). Springs from the posterior half of the upper region of the outer surface of the scapula. It passes down, with converging fibers, to unite with the latissimus dorsi muscle to form a strong tendon that is inserted on the extensor surface of the humerus. _Subscapularis_ (Unterschulterblattmuskel). Springs from the inner surface of the scapula, except from the suprascapula, goes with converging fibers directly over the capsule of the shoulder joint to be attached to the medial process of the humerus. _Anconæus._ This strong muscle lies on the extensor side of the upper arm. It is made up of two layers: the superficial comes from the pectoral girdle in two heads: (a) the caput scapulare laterale externum and (b) caput coraco-scapulare; the deeper layer originates on the humerus by three heads, (c) caput humerale laterale, (d) caput humerale posticum, and (e) caput humerale mediale. These five heads of the anconæus muscle with their synonyms will now be described. (a) _Caput Scapulare Laterale Externum_ (Plate I., Figs. 1 and 4, asl) (Brevi proximum caput m. tricipitis, Gewöhnlicher [äusserer] langer Kopf des dreiköpfigen Streckers, Portion scapulaire externe du triceps-brachial, Erster langer Kopf des Triceps, [Zweiter] abducirender vom Schultergerüst entstehender Kopf des Streckmuskels des Vorderarmes, Triceps Nr. 1, Triceps longus). This muscle springs as a tendon from the hinder border of the scapula directly beneath the articular cavity, and extends back, between the scapulo-humeralis profundus and the dorsalis scapulæ muscles, into the muscle belly. (b) _Caput coraco-scapulare_ (Plate I., Figs. 2, 4, 5, 6, acs) (Externum caput m. tricipitis, Innerer langer Kopf des dreiköpfigen Streckers, Portion scapulaire interne du triceps-brachial, Zweiter langer Kopf des Triceps, [Erster] abducirender vom Schultergerüst entstehender Kopf des Streckmuskels des Vorderarmes, Triceps Nr. 2, Triceps longus secundus). Arises by two distinct tendinous tips--the upper, weaker one from the hinder border of the scapula, the lower, broader one from the hinder border of the coracoid. (c) _Caput Humeri Laterale_ (Plate I., Figs. 1 and 4, ahl) (Brevius caput m. brachiei interni, [Aeusserer] kurzer Kopf des dreiköpfigen Streckers, Portion huméral externe du triceps brachial, Aeusserer vom Humerus ausgehender Kopf des Streckmuskels des Vorderarmes, Theil des Triceps Nr. 3, Triceps externum). Springs from the lateral part of the extensor surface of the humerus dorsal to the lateral process and the origins of the humero-radialis and brachialis superior.