The superficial or perforated flexor muscle passes down the front of the forearm and divides into four tendons, which become apparent after the removal of the palmar fascia, and are inserted into the second phalanges of the fingers, each tendon splitting at its termination, to give passage to the similar tendons of the deep or perforating flexor muscle, which passes from the upper part of the ulna to be inserted into the last pha lanx of each finger. These flexor muscles are antagonized by the common extensor muscle of the fingers, which, like the flexors, divides into four tendons, one for each finger. Besides these, there is a special extensor of the index-finger, a series of muscles forming the ball of the thumb, which move that organ in almost every direction, and various small slips giving lateral and other movements to the fingers.
It is sufficient to observe that the hand is very richly supplied with blood-vessels and nerves, without entering into any anatomical details on these points. There is no part
of the body where the sense of touch is so acute as at the tips of the fingers; but we shall defer to the article TOUCH, ORGANS AND SENSE or, the consideration of the special arrangements which make this part of the hand peculiarly important in relation to our knowledge of external objects.
Our notice of the comparative anatomy of the foot (q. v.) renders it unnecessary to trace the modifications presented in the lower animals by the 'bones corresponding to those of the human hand; as the carpal and metacarpal bones with their phalanges undergo adaptations of form to meet the individnal wants of the animal, very much in the same manner as the tarsal and metatarsal bones and their phalanges. Thus, the reader will readily see that the so-called knee of the horse, for example, is the and he will have no difficulty in tracing the metacarpal bones and phalanges. bee the articles BnoliEri KNEES and HousE; and Humphry, On the human Foot and Human. Hand.