(From flecto, to bend). A name applied to several muscles, from their office of bending the parts to which they belong.

Flexor brevis minimi digiti manus, rises from the unciform process of the carpus, toward the annular ligament, and is inserted into the basis of the little finger.

Flexor capitis. See Rectus internus major.

Flexor carpi radialis; flexor carpi exterior, and bicornis; rises from the anterior part of the inner condyle of the os humeri, passes toward the outside, and runs through the annular ligament, being partly inserted into the trapezium, and partly into the first metacarpal bone.

Flexor carpi ulnaris, flexor carpi interior, rises from the inner condyle of the os humeri, and almost from the whole surface of the ulna, forming a tendon inserted into the os pisiforme.

Flexor digiti parvi minimi. See Abductor minimi digiti manus.

Flexor digitorum accessorius. See Flexor lungus pedis. Dr. Hunter calls it accessorius.

Flexor digitorum pedis. See Flexor subli-mis.

Flexor secundi internodii digitorum pedis. See Flexor sublimis.

Flexor internodii primi digitorum. See Lum-bricales. Dr. Hunter describes the lumbricales as productions of the flexors, and distinctly that called

Flexor internodii primi pollicis manus, rising from the annular ligament of the carpus, and inserted into the first bone of the thumb.

Flexor internodii primi et secundi pollicis. These muscles rise sharp and fleshy about the middle of the back part of the fibula; then, running into a tendon in passing over the joint, and through a channel in the inner part of the os calcis, are inserted into the upper end of the second bone of the great toe.

Flexor internodii secundi digitorum manus, flexor sublimis, or perforatus, rises from the inner condyle of the os humeri, and from the fore part of the head of the ulna and radius; passes through the annular ligament, and spreads out into four tendons, which are inserted into the basis of the second phalanx: these are bound down by what is called an annular ligament, which is really a general sheath of the fingers, thicker at the joints than elsewhere. Brown calls this muscle flexor secundns.

Flexor internodii secundi pollicis manus, is made up of two portions, the anterior of which is inserted into one sesamoid bone, the posterior into the other.

Flexor internodii tertii digitorum manus, by Dr. Hunter called perforans manus; profundus manus; rises from the inner condyle of the os humeri, from the external part of the ulna about its middle, and from the interosseous ligament; runs between the perforata, and forms four tendons, which pass through as many slits in the perforatus, to be inserted into the basis of the last phalanx.

Flexor internodii tertii pollicis, vel longi's-simus pollicis manus, hath sometimes a twofold beginning; one from the internal substance of the os humeri, between the perforatus and perforans, but this head is occasionally wanting; or springs from the upper and fore part of the ulna: the second head rises on the radius, passes over the articulation of the carpus, and is inserted in the upper part of the third bone of the thumb.

Flexor longus, or perforans pedis, called also accessorius, rises from the posterior part of the tibia, just below the poplitaeus, and from the interosseous ligament; goes on the inside of the astragalus and os calcis (from whose internal part a short head arises, called accessorius), and passing through the slit of the perforatus, its four tendons are inserted into the basis of the last bones of the toes. This muscle receives some fibres from the flexor pollicis longus.

Flexor perforans manus. See Flexor internodii Tertii Digitorum Manus.

Flexor pollicis brevis, is short, thick, and fleshy, seemingly divided into two muscles, by the tendon of the flexor pollicis longus passing over it. It rises from the upper part of the os cuneiforme medium, and, running over the termination of the musculus pe-ronaeus primus, is implanted into the ossa sesamoidea of the great toe, which are likewise tied to the superior part of the second bone of that toe.

Flexor pollicis longus manus, rises from the fore part of the radius, and commonly receives one slip from the coronoid process of the ulna; forming a tendon which passes deep under the annular ligament, runs between the two sesamoid bones, over the first and second bone, to be inserted into the basis of the third.

Flexor pollicis longus pedis, rises from the posterior part of the fibula; passes in a groove between the astragalus and os calcis; is covered by the abductor pollicis, and goes between the sesamoid bones, where it meets with an annular ligament, to be inserted into the last bone of the great toe. It gives some fibres to the perforans pedis.

Flexor pollicis ossis primi et secundi, is a large disgregated muscle, arising from the ligamen-tum transversale carpi, the bones of the carpus at the basis of the mons lunae, and the os metacarpi of the middle finger, whence it passes to its insertion into the first and second bones of the thumb. In its tendon, near the insertion into the first bone of the thumb, are placed two sesamoid bones. Its actions are various, as are the directions of the muscular fibres.

Flexor sublimis, or perforatus pedis, called by Winslow, flexor digitorum brevis, and by Brown, flexor secundi internodii digitorum; rises from the lower and inner part of the os calcis; is divided into four tendons under the sole of the foot, which are inserted into the bones of the second phalanx.