572 . MR. J. C. GALTON ON THE MYOLOGY OF 



means of a slight, but distinct, downward prolongation of some of its fibres, from the 

 terminal aponeurosis of the rectus abdominis, which finds insertion at the first rib. 



It then passes, rolled upon itself, under the clavicle, to be inserted aponeurotically 

 along the upper border of the acromial half of this bone, into a kind of sesamoid 1 situated 

 just below the acromioclavicular joint, and which is imbedded in the fibres of origin of 

 the deltoid, along the acromion itself, and into the fascia covering the supraspinal 

 muscle; while a thin stratum, derived from the lower portion of the muscle, finds inser- 

 tion by aponeurosis along the inner edge of the strong coraco-acromial ligament. 



This mode of insertion of the subclavius bears great resemblance to that of its homo- 

 logue in the species of Dasypus already described by me. 

 The muscle, at its insertion, is fairly represented by Cuvier in one of his plates 2 . 

 Prof, llolleston considers that the ventral portion of the muscle, through the inter- 

 mediation of fascia covering the external surface of the acromion, can act, as in the 

 Gumeapig, upon the acromial portion of the deltoid. 



With regard to the significance of the origin of part of the subclavius from the terminal 

 tendon of the rectus abdominis, and its bearings upon the possible homology of the 

 former muscle with the levator humeri of Birds, both detail and generalization will be 

 found in a forthcoming paper by Br. Rolleston « on the Homologies of certain Muscles 

 connected with the Shoulder-joint" 3 . 



I could not determine with certainty, in the specimens of Dasypus sexcinctus which I 

 examined, whether the lowest fibres of origin of the subclavius were in any wise conti- 

 nuous with the terminal fibres of the rectus abdominis, which muscle had a fleshy 

 ^!rl < ^ a P° neurotic ) inserti0 * ^ the first rib, at the very foot of the origin of the 



Though not strictly a muscle of the upper limb, it may not be 



subclavius 4 . 

 Obliquus exi 



out of place to 



that it extends very high over the chest, its aponeurosis 



the recfm abdominis almost up to the termination of this latter 



Its hi 



fibres of origin arise from the upper edge of the first rib, between the origin of tte «d 



ascertain, for the support or the establishment „f „ • 2 . . J ""*• ltouc8ton > «">' wlstim « » 



the specimen which I ™ 7 , a ™ ent ° f an lm ' >ortant anatomical point, the termination of the subchaius in 



Tho «' Z^SirJS* £££ 7 de J " ~ <* — » *» ' W I—* acne. 



ascribed b y CW in hi 8 . (Jem ns Z ilfs ? Z T "° T™ "' * ^^ ' "" " * **"* " 

 reference to such a bone ■ nor I. «*. PP ' m o 8 ' 001 ^^ portion of bia monograph, mokes no 



of Surgeons. ' *T ° M I—* « «* ««•«. i» the skeleton of 0,-ycUr,,,,,,, at the Eoyal CoUege 



h. *; \ SKsi? , - 5r£ zxt? aml : ,CTciopmcnt ° f ^ ***** * *— 



Orytorvv, nor does he represent it in his fi„ £5 T Tf?. * "" " C ° "' ^ "^ h ^ 



though the specimen from which these were taken is described as 



lne c -lcle, if not a " sesamoid," ma 

 of the above-quoted monograph . 



2 Op. cit. pi. 256. fig. 5. 



3 Trans. Linn. Soc. vol. xxvi. 1868. 

 * Meckel (Vergleich. Anat. he. cit. p. 



" ohne Ur.terbreclmng," to the first rib. 



ii 



old." 



segment 



described b}- Mr. Parker at p. 195 





Armadillo 



