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 Part I. i8o A N A T O M Y. os fcaphoides, lunare, cnneiforme, fijiforme, trapezium, unciform bone, and to the os metacarpi of the little finger, are attached to its lower part; the abdudlor minitrapezoides, magnum, unciforme. The fcaphoides is fituated moft internally of thofe that mi digiti has its origin from its fore-part; and, at the are articulated with the fore-arm.—The lunare is imme- internal fide of it, a fmall depreffion is formed, for the diately on the outfide of the former.—The cuneiforme paffage of the ulnar nerve. is placed ftill more externally, but does not reach fo high Trapezium has four unequal fides and angles in its up as the other two.—The pififorme Hands forwards in- back-part, from which it has got its name.——Above, to the palm from the cuneiforme.—The trapezium is the its furface is fmooth; flightly hollowed, and femicirfirft of the fecond row, and is fituated betwixt the fca- cular, for its conjundlion with the os fcaphoides. Its phoides and firlf joint of the thumb.—The trapezoides is external fide is an oblong concave fquare, for receiimmediately on the outfide of the trapezium.—The os ving the following bone. The inferior furface is 'magnum is ftill more external.—The unciforme is far- formed into a pulley ; the tv/o protuberant fides of which are external and internal. On this pulley the ther to the fide of the little finger. Os fcaphoides is the largeft of the eight except one. firft bone of the thumb is moved. At the exterIt is convex above, cOncave and oblong below; from nal fide of the external protuberance, a fmall oblong which fmall refemblance of a boat it has got its name.— fmooth furface is formed by the os metacarpi indicis. Its fmooth convex furface is divided by a rough middle -—The fore-part of the trapezium is prominent in the foffa, which runs obliquely crois it.—The upper largeft palm, and, near to the external fide, has a finuofity in divifion is articulated with the radius.—Into the fofla it, where the tendon of the flexor carpi radialis is lodthe common ligament of the joint of the wrift is fix- ged ; on the ligamentous flieath of which the tendon of ed; and the lower divifion is joined to the trapezium the flexor tertii internodii pollicis plays: And ftill more and trapezoides.—-The concavity receives more than an externally the bone is fcabrous, where the tranfverfe lihalf of the round head of the os magnum.—The external gament of the wrift is conne&ed, the abdudtor and flexor fide of this hollow is formed into a femilunar plane, to primi internodii pollicis have their origin, and ligaments be articulated with the following bone.—The internal, go out to the firft bone of the thumb. pofterior, and anterior edges are rough, for fixing the Os trapezoides, fo called from the irregular quadrangular figure of its back-part, is the fmalleft bone of the ligaments that conned it to the furrounding bones. Os lunare has a fmooth convex upper furface, by wrift, except the pififorme.—The figure of it is an irrewhich it is articulated with the radius. The internal gular cube.—It has a fmall hollow furface above, by fide, which gives the name to the bone, is in the form of which it joins the fcaphoides; a long convex one intera crefcent, and is joined with the fcaphoid ;-—the lower nally, where it is contiguous to the trapezium ; a fmall furface is hollow, for receiving part of the head of the. external one, for its conjunction with the os magnum ; os magnum. On the outfide of this cavity is an- and an inferior convex furface, the edges of which are other fmooth, but narrow oblong finuofity, for receiving however fo raifed before and behind, that a fort of pulthe upper end of the os unciforme:—On the outfide of ley is formed, where it fuftains the os metacarpi indicis. which a final! round convexity is found, for its con- Os magnum, fo called becaufe it is the largeft bone of nedion with the os cuneiforme. Between the great con- the carpus, is oblong, having four quadrangular fides, vexity above, and the firft deep inferior cavity, there is with a round upper end, and a triangular plain one bea rough foffa, in which the circular ligament of the joint low.—The round head is divided by a fmall rifing, oppofite to the connection of the os fcaphoides and lunare, of the wrift is fixed. Os cuneiforme is broader above, and towards the back which together form the cavity for receiving it.—On the of the hand, than it.is below and forwards : which gives infide, a flrort plain furface joins the os magnum to the ft the refemblance of a -wedge. The fuperior flightly trapezoides.—On the outfide is a long narrow concave convex furface is included in the joint of the wrift, be- furface, where it is contiguous to the os unciforme. ing oppofed to the lower end of the ulna.—Below this, The lower end, which fuftains the metacarpal bone the cuneiform bone has a rough foffa, wherein the liga- of the middle finger, is triangular, flightly hollowed, ment of the articulation of the wrift is fixed.—On the and farther advanced on the internal fide than on the internal fide of this bone, where it is contiguous to the external, having a c'onfiderable oblong depreflion made os lunare, it is fmooth and fiightly concave.—Its lower on the advanced infide by the metacarpal bone of the furface, where it is contiguous to the os unciforme, is ob- fore-finger; and generally there is a fmall mark of the long, fomewhat fpiral, and concave.—Near the middle os metacarpi digiti annularis on its external fide. of its anterior furface, a circular plane appears, where the Os unciforme has got its name from a thin broad procefs that Hands out from it forwards into the palm, and os pififorme is fuftained. Os pififorme is almoft fpherical, except one circular is hollow on its infide, for affording paffage to the tenplane, or flightly hollow furface, which is covered with dons of the flexors of the fingers. To this prtcefs alfo cartilage for its motion on the cuneiforme bone, from the tranfverfe ligament is fixed, that binds down and which its whole rough body is prominent forwards into defends thefe tendons; and the flexor and abduCtor the palm; having the tendon of the flexor carpi ulnaris, mufcles of the little finger have part of their origin from and a ligament from the ftyloid procefs of the ulna, fixed it.-»-The upper plain furface is fmall, convex, aad jointo its upper part; the tranfverfe ligament of the wrift is ed with the os Junare:—The internal fide is long, and £oone<fted to its internal fide; ligaments extended to the flightly convex, adapted to the contiguous os magnum :