MINGLES OF THE TRUNK. 197 



.md tin- tr:i"helo-a'Toniialis peculiar to quadruped mammals 1 G. Cuv'er, ' Lemons 

 d'Anatoinii- Comparee,' 2od ediiion. (This is tin- mn.-H.- whii-h IVrrivall names the 

 ln-iit <>r humtrl. Tin- ulmve is tin- di -M^nation Lrm-n to it l.y (iirard and Cbauvcau. 

 I.r\li ir,\. ? it tin- .-am.- diMipiatiou oa 



Est''nt Situation Direct ion Composition. This muscle extends from 

 the summit of the bead to the inferior part of the arm, and is applied to the 

 scupulo humeral angle at the side of the neck, in an oblique din etion down- 

 wards and backwards. It is composed of two portions lying longitudi- 

 nally and somewhat intimately united, and distinguished into anterior and 



Structure Attachments. A. The anterior or superficial portion 

 (Fig. 10G, 6) constitutes a long fleshy band, which appears to be united, by 

 its anterior border, to the cuticular muscle of the neck. Its superior 

 extremity, thin and wide, is attached to the mastoid process and crest by an 

 aponenrosis (Fig. 102, 7), which is united, in front, to the tendon of the 

 sterno-maxillaris by a very thin cellulo-aponrurotic fascia. Its inferior ex- 

 tremity, thicker than the superior, is inserted by means of a very short 

 aponeurosis into the humerus, on the salient border descending from the 

 deltoid imprint, and which limits, in front, the furrow of torsion on the 

 body of that bone (Fig. 102, 7). 



B. The posterior or deep portion (Fig. 102, 9) is a second muscular band, 

 shorter and stronger than the preceding. It is attached, above, to the 

 transverse processes of the first four cervical vertebrae by as many fleshy bands 

 i Fig. 102, 8'), which cover the superficial portion. The upp^r digitation, 

 given off to the atlas, is united to the tendon common to the small complexus 

 and splenius (Figs. 105, 9; 106, 9 f , 10, 11). The inferior extremity of this 

 portion of the muscle widens on the scapulo-humeral angle, which it 

 envelops in becoming closely united to the anterior portion, terminating 

 with it on the humerus. An aponeurosis, which is confounded with that of 

 tin; trapezius, and scuds off a septum into the interstice between the two 

 portions of the long abductor of the arm, concurs to fix this extremity by 

 spreading over the muscles of the arm. 



Relations. It is covered, near its mastoid insertion, by the parotid gland 

 and the cervico-aiiricularis muscles; for the remainder of its extent, by the 

 a pi 'neurosis of the cuticularis colli, from which it is separated by a thin 

 tinuous with that which extends over the trapczius. It covers the 

 splenius. the small complexus, the oblique muscles of the head, subscapulo- 

 hyoideus (to which it adheres intimately), the digastricus, long flexor of the 

 head, the angularis, scaknus. small pectoral, supra- and infraspinatus, the 

 long abductor of the arm, and the coraco-radialis. 



1 At tii>t Mirht \M- mil-lit In Mtat<- t'p admit that this nnisde is formed of such varied 

 and o'injili"-at. <1 c 1. im-nts as are enmuenited above. Nevnt!n-lrss, it is a soii-ntinV I'a.-i ; 

 and we \sill _-i\> a ! nion.-tnttioii, us (.imple as it is clear, that sin-h i.* tli 

 id< a we owe to J. F. Mn-k' 1. It t.ik. tin- !>:_'. l<>r xmujile, ami .-ii|.|xse it to bo 

 possessed of a clavicle rxti-ndini.' from tin- anterior Mr- mity of tin- tsternum to the 

 ii<Tiiinio:i ; this claviele would cut. 1 ran>vi r-t 1 y. tin- inl'i rior p-rtion <.f tli<- nin-' 

 bumenlu, which WOQld tbm Ke dividi-il into two jM.itioiK*, a f-njH-rior and an inferior. 

 \ti-nuiir_' from tin- clavii-le to the nm-toid |>P <. on this side, and on the 

 tli.-r to the mMtoid creit, U \\.-ll us t<> th.-e.i \ical ligament, whi-n- it i- (t.|il..undrd with 

 the tmj>-y.ii!s, would iM.f-tlv n ]in . nt the flavicular portion at the latt.-r mu>. ! 

 ill. , .,/,x. \Vi; i ' tin- in'i-iior iMiition, it prl. <-tl> n .--ml'l. ... l.y its 



.ni.-nt^ th. iliirirnl.ir /...r/iV.n of the di-ltoid. Hut. on the mtiary. if \\. D 

 i.-pm.d of :i <-l;i\i,-lr, the thr..- miiM-iiliir fawteiili inliiat.d. in l>i-i-iiii,in<; e.m- 

 found.-d \>iih . a-h other, would form the niii*tojdo-liumi-r.di.s ot th POL:, mil, 

 .-r portion, or the tnohelo-acromialis, whieh i not reiin.-nt. d in M.in 



