. Quain's Elements of anatomy. verse ridge of the front ofthe lower extremity, and to which the posterior annular li^rament is attached, while posteriorlyit is limited by a less marked elevation descending;: on the back of the styloid process. The•rroove of the extensor longus pollicis is bounded externally by the tubercle, internally by asmall, often indistinct, ridjie ; and a sharp border projects between the innermost {jroove andthe si-rmoid cavity. The several prominences <;-ive attachment to fibrous septa, which withthe annular li^jament convert the j,rooves into canals for the passaj^
. Quain's Elements of anatomy. verse ridge of the front ofthe lower extremity, and to which the posterior annular li^rament is attached, while posteriorlyit is limited by a less marked elevation descending;: on the back of the styloid process. The•rroove of the extensor longus pollicis is bounded externally by the tubercle, internally by asmall, often indistinct, ridjie ; and a sharp border projects between the innermost {jroove andthe si-rmoid cavity. The several prominences <;-ive attachment to fibrous septa, which withthe annular li^jament convert the j,rooves into canals for the passaj^e of the tendons. The radius is for the most part deeply placed. The head and shaft are entirelycovered by muscles. At the lower end the styloid process comes to the surfacebetween the tendons of the extensor muscles of the thumb and forms a projection onthe outer side of the wrist, lower down than the styloid process of the ulna : thetubercle on the back of the lower end of the bone may also be readily felt beneaththe The relative lenjrth of the forearm to the arm is expressed by the liumcyd-rddidl or anti- , 7 • I • 7 /len^th of radius x 100\ ,, ,. ^. ^ , • i • j , bracluai uitlcrl ). the rantre oi variation of which in man and the V. lenjrth of humerus / anthropoid apes is shown by the followinjr examples, viz.—Eskimo, 71 ; European, 74 ; Australian. 77 : Netrro. 7!): Andamanese, 81 ; gorilla. 80; chimpanzee. !)0 ; and orang, 100. The index is higher in the tVctus and infant, and diminishes during the period of growth. H 2 100 THE BONES OF THE UPPER LIMB. a?HE CARPUS. The carpus is composed of eight short bones, which are disposed in two rows,four in each. Enumerated from the radial to the ulnar side, the bones which con-stitute the first or superior row are named scaphoid, lunar, pyramidal, and pisijorm,those of the second or inferior row are the trapezium, trapezoid, os magnum, andtmciform. The dorsal surface of the carpus is convex, the palmar is con
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Keywords: ., bookcentury1800, bookdecade1890, bookpublishe, booksubjectanatomy
