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Artery arising from the brachiocephalic trunk on the right side and from the arch of the aorta on the left side. It distributes to the neck, thoracic wall, spinal cord, brain, meninges, and upper limb.

Are situate at the upper part of the chest, and the lateral and lower parts of the neck. The right arises at the corresponding side of the trachea, and comes off from the arteria innominata or brachio-cephalic trunk. The left leaves the aorta at the end of the arch. Both extend as far as the superior surface of the first rib, in the space between the scaleni muscles, beyond which they take the name axillary arteries. The subclavian arteries run, for some distance, without sending off any branch. In the neigh-bourhood of the first rib, however, they give off, 1. Upwards, the vertebral and inferior thyroideal. 2. Downwards, the internal mammary and superior intercostal. 3. Outwards, the transverse cervical or posterior scapular, the superior scaptdar, and the posterior cervical or profunda.