MR. J. C. GALTON ON DASYPUS SEXCINCTUS. 



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of the radius, at the junction of the proximal with the middle third of this bono, and 



immediately posterior and external to the insertion of the broad tendon of thepron w 



teres, widening out and becoming natter at its termination. 



This muscle is not represented by Cuvier in his plates of the myology of Doty pus. 



Both short and long supinators appear, according to Ueekrl, to be fa 

 (" verschmolzen zu seyn"). He remarks further that no muscle is given ofT from 

 humerus above the extensores of the hand. Under these, on the other hand, 

 stronger muscle, which passes to the upper hall' of the radius, "und Moss 1 

 In all probability the long supinator is absent in this animal (Dasy}, s) ; and the ah 

 muscle may be, after all ("nur"), the short su)>i„ator\ 



e, in their paper on the " 



ies a muc 



euirer ist. 



• • 



Mr. Mivart and Dr. Mur 



Myology of J I v rax co-pen 



describe as supinator longus a muscle which much resembles that which I have termed 



s. brevis in D 



It is "exceedingly diminutive, and arises from the outer shaft of 



the humerus, just above the common origin of the next two muse I < - (c.i tensor Car}, 

 radialis and e. communis), and is inserted into the radius near its neck." 



Soemmering 3 , in his description of this muscle in man, sa\ >, " Nonnumquam superior 

 pars [humeral origin] a reliquo musculo distinct a est." 



Theile, moreover, states that when the two layers of which the muscle is composed are 

 distinct, the superior head takes origin from the outer condyle of the In 



Extensor carpi radialis 



unerus . 



From the strong outer ridge ("supinator ridge") of the 



humer 



for the extent of nearly three quarters of 



ts superior 



portion, a muscle which, after completing about half of its course, crosses over the radiu 

 and, becoming suddenly tendinous at the distance of an inch from its insertion, passes 

 under a ligamentous and muscular bridge into the palm, 

 stretches from the abrupt spinous termination of the dorsal ridge of the rad 



The ligamentous bridge 



sesamoid ly 



midway between this point and the styloid pi 

 metacarpi pollicis forms the muscular bridge. 

 Two cord-like tendons are given off simultaneously by tlii 



of the bon 



The 



rtusclc, which, hefo 



: one of these 



becoming tendinous, narrows more or less suddenly to a conical apex; one 

 inserted into the dorsal surface of the metacarpal of the index, while the other termi- 

 nates at the same aspect of the like segment of the middle digit. 

 These answer respectively to the tendons of the extensores carp, wholes, longior ei 



brevior, of human-anatomy language. 

 It is stated in Cuvier's « Lecons " 

 Hare, and the Edentata, the above 

 tremity, their tendons alone being distinct 



that in some animals, such as the Dog, Hys 

 muscles are fused together at their condyloid 



adialis brevior is occasionally absent in man, as is 



Zmals "m which never more than one radial extensor is met with. 



continues, << dont le premier degre est la fusion complete de deux 



Meckel observes that the extensor 



the case in many m 



"Conformation," he ^~ — _ -~, - 1 



radiaux externes en un seal, dont on connait divers exemples 



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Op. tit. p. 534. 



De Corp. Humani Fate; torn. iii. p. 267. 



Loc. cit. d. 443. . 



Soc. April 18 

 lie Anatomiqu 

 inatomie Gent 



103. 



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