THE DERMAL MUSCLES. 



11 



Reflect back on either side the integumental flaps, as 

 far as the sides and the Jimbs. Several muscles of the 

 cutaneous system are now exposed in this region. 



9. The der mo- spinalis. — This delicate muscle is but 



Fig. 2. — Sujierior aspect of the skull of Raven, adult $, life-.size. ]\Iandible 

 removed. Shows the upper edge of the insertion of the temporal muscle, 

 and that part of the masseter which arises on the zygoma. 



feebly developed in the Raven, but a little staining in 

 old males will usually bring its fibres into view. It 

 arises in an attenuated fascia from the crests of the 



