4 THE MYOLOGY OF THE RAVEN. 



end of this make an incision backwards down to the 

 skull, and posteriorly to well expose the muscles in the 

 upper part of the neck. This straight cut should pass 

 about half a centimetre to the inner side of the upper 

 eyelid of the same side. Reflect the flap of integu- 

 ment thus formed, covering the top of the skull, and 

 carefully examine the under side of it in the median 

 line, where it overlies the frontal region. In old male 

 Ravens, I have here found a true dermal muscle, some 

 3 centimetres long, and a few millimetres wide, closely 

 attached to the skin. So far, it has not been observed 

 by me in female birds. By its contraction, the median 

 feathers on the top of the head are made to lie very 

 flat ; at the same time those immediately above either 

 eye are elevated, thus giving rise to lateral crests, which 

 are quite well marked. In a captive Raven, an old adult 

 male, I have seen the bird during certain moods make 

 these crests stand up so as to be very evident, not to 

 say conspicuous. 



2. The circumconcha. -This is a dermo-osseous muscle 

 which surrounds the periphery of the ear-conch. To 

 expose it, join the longitudinal incision we have already 

 made, and carry the scalpel just through the integument 

 completely around the ear, a few millimetres without its 

 thickened margin ; then dissect carefully up from all 



simply inviting attention to the fact that my dermo-temporalis 

 appears to be the second division of the M. CUCULLAEIS of Gadow ; 

 the dermo-dorsalis being also a part of the same ; while the 

 platysma myoides of my list is the first division of the m. cucullaris 

 of the same writer ; and finally, my dermo-tensor patagii is the PAUS 

 PROPATAGIALIS of the M. cucuLLAEis of Furbringer. The skin 

 muscles in the neck of birds have been quite extensively divided up 

 by Gadow and Fiirbringer, described under a superficial and deep 

 set, and in the main as constituting various parts of their m. 

 cucullaris (Bronn's Klassen, vi. Band, 11 u, 1 2 Lieferung, p. 214). 



