Henry Gray (1825–1861). Anatomy of the Human Body. 1918.
pages 1329
| a zigzag line with a general convexity forward; when the arm is by the side the highest visible serration is that attached to the fifth rib. |
| The Deltoideus with the prominence of the upper end of the humerus produces the rounded contour of the shoulder; it is rounded and fuller in front than behind, where it presents a somewhat flattened form. Above, its anterior border presents a slightly curved eminence which forms the lateral boundary of the infraclavicular fossa; below, it is closely united with the Pectoralis major. Its posterior border is thin, flattened, and scarcely marked above, but is thicker and more prominent below. The insertion of Deltoideus is marked by a depression on the lateral side of the middle of the arm. |
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FIG. 1231– Front of right upper extremity. (See enlarged image) |
| Of the scapular muscles the only one which influences surface form is the Teres major; it assists the Latissimus dorsi in forming the thick, rounded, posterior axillary fold. |
| When the arm is raised the Coracobrachialis reveals itself as a narrow elevation emerging from under cover of the anterior axillary fold and running medial to the body of the humerus. |
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FIG. 1232– Back of right upper extremity. (See enlarged image) |
| On the front and medial aspects of the arm is the prominence of the Biceps brachii, bounded on either side by an intermuscular depression. It determines the contour of the front of the arm and extends from the anterior axillary fold to the bend of the elbow; its upper tendons are concealed by the Pectoralis major and Deltoideus, and its lower tendon sinks into the anticubital fossa. When the muscle is fully contracted it presents a globular form, and the lacertus fibrosus attached |