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Show 710 MR. T. MANNERS-SMITH ON THE [DeC. 4. ficial extensor is supplied by the same nerve which supplies the extensor indicis. There is a distinct extensor for second digit arising from upper expanded extremity of fibula, from head of bone, and from a tendinous band between these two points; it is supplied by a slender branch from the peroneal nerve. It will be noticed that index receives three tendons-one from superficial extensor, one from deep, together with a special extensor. Tibialis anticus.-Arises by two heads: a superficial from upper expanded extremity of fibula, from a strong tendinous band passing from fibula to patella, from patella itself, and from tibia. The deep head from shaft of tibia. It is inserted into ento-cunei-form. Both heads are supplied by a nerve from the front of the thigh, which passes beneath the above-mentioned tendinous band. Peroneus longus.-Arises from the upper expanded extremity of the fibula. Passing down the outer side of the leg, it reaches the interval between the large os calcis and the cuboid, and passes deeply into the sole of the foot, traverses the sole, and is inserted in the usual situation. It is supplied by the peroneal nerve. Peroneus brevis.-Arises beneath longus from the expanded extremity of fibula. Its tendon divides beloAV into two slips, one passing to first, the other to second phalanx of fifth toe. It is supplied by the peroneal nerve. Coues describes this as peroneus tertius. Its origin and nerve-supply Avould rather correspond to that of brevis. MYOLOGY OF PES. Of the muscles of the big toe, flexor brevis hallucis is the only one which can be made out, and this is extremely small. Of muscles of the litttle toe, the flexor brevis, the adductor, and the abductor, and a small abductor minimi digiti can be made out. Plantar and dorsal inter-ossei are also present. PLEXUSES. Brachial plexus.-This is formed by the fifth, sixth, seventh, eighth cervical and first dorsal nerves. There is a small filament, in addition, from the fourth cervical, and the first dorsal receives a small branch from the second. The plexus consists of two main trunks-an upper and a lower.* The fifth and sixth unite and form the upper trunk. Immediately beyond the formation of this trunk two nerves arise: one passes upwards and forwards and, joining the branch to the plexus from the fourth cervical nerve, it is distributed to the so-called infra-spinatus muscle; the other nerve passes downAvards and backwards and forms one head of median. The trunk itself passes backwards in a somewhat similar manner to the circumflex of human anatomy, gives off a branch to subscapularis, and divides into two parts-one passes into forearm and supplies the skin on the outer posterior aspect of the |