140 



THE CAT. 



[CHAP. v. 



one side act alone, the whole backbone is flexed towards the side of 

 such action. 



The levatores costarum are small groups of fibres passing obliquely 

 backwards from the dorsal transverse processes to the respective ribs 

 at their proximal parts. 



Layers of fibres extending obliquely from rib to rib are called 

 " intercostal muscles," and there are two sets of them, one inner, 

 the other outer (Fig. 78). 



The external intercostals are more dorsally situated, since each 



S/iy 



-Jo 



Ex.o 



Fig. TO. MUSCLES OF VENTRAL SURFACE OF TRUNK THE LEFT FORE-LIMB AND LEFT PECTORAL 

 MUSCLES BEING REMOVED. 



CM. Cleido-mastoid. 



Cv. Clavicle. 



D 3 . Deltoid. 



Ed. External dorso-epitroclilear. 



Exo. External oblique. 



Id. Internal dorso-epitrochlear. 



Jo. Internal oblique. 



Ld. Latissimus dorsi. 



Pi, P 2 , and P\ Pectoralis. 



/,'. Rectus abdominis. 

 .S'c 1 . Scalenus primus. 

 ,S'c 2 . Scalenus secundus. 

 Shy. Sterno-hyoid. 

 Sm. Serratus niagnus. 

 St l . Sternalis. 

 ,S< 2 . Second sternalis. 

 St. m. Sterno-mastoid. 



such intercostal connects two ribs, all the way from their tubercles 

 to their cartilages. Their fibres are directed backwards and down- 

 wards (i). 



The internal intercostals have their fibres directed backwards and 

 upwards, and the sheet of such fibres which connects each pair of 

 ribs reaches from the sternum upwards as far as the angles of the 



