44 ANATOMY or THE RABBIT 



dorsi muscle (No. 2, p. 49) in the axilla, sternum amd linea 

 alba and inserts in the skin along the dorsolateral body region. 

 The platysma muscle covers much of the side of the head and 

 neck. It arises mainly from the ventrum of the head and neck, 

 whence its fibers are distributed dorsocaudad to the skin. The 

 platisma is sometimes described as two muscles, the "super- 

 cervicocutaneous " and the ''cervicofacial" which approximates 

 the platisma of man. The function of the subcutaneous 

 muscles is principally to move the skin. In removing the 

 cutaneous maximus m. it is best to leave it attached to the 

 distal end of the latissimus dorsi m. until after the limb has 

 been removed from the body. 



H. PREPARING THE SKINNED SURFACE FOR 

 DISSECTION OF THE MUSCLES 



Before beginning the actual dissection of the muscles (Chapter 

 V) the superficial fascia and fat must be cleared away from the 

 region to be dissected so that the borders of the muscles can be 

 accurately distinguished. This is best accomplished with the 

 thumb nail and forefinger, or with the cartilage knife and 

 thumb, by means of which the tissue is stripped off the muscles. 

 Avoid the practice common to many beginners of picking up 

 the fascia with forceps and then cutting it off, for this invariably 

 results in nicks being cut out of the muscles instead of a smooth 

 uniform surface. After the surface has been cleared properly 

 the border of a muscle will stand out as a line of demarkation 

 which may be indicated simply as a line of inaction when the 

 member is manipulated, or as a definite line of tangency 

 between fibers of a muscle running in one direction and those 

 of another muscle passing in a different direction. That is, 

 the fibers of one muscle are all parallel, usually. Of course there 

 are exceptions to the rule. Often the margin of a muscle is 

 dehmited by fat lying between it and the next muscle. When 

 the border of the muscle has been definitely determined probe 

 under it with the grooved director to determine the depth of 



