OUR FACE FROM FISH TO MAN 



lower jaw. In the fossil mammal-like reptiles a 

 large notch (Figs. 112, 113) in the back of the 



B 



A/)JG 



ART/Cf(MALLEUS) 



CARTILAGE 



■qi/'(/m:us) 







Fig. 113. Origin of Auditory Ossicles. 



(A) Back part of the lower jaw of an advanced mammal-like reptile 

 (based chiefly on a cast of the specimen combined with observations 

 and figures of Seeley and Watson); (B) Foetal mammal (slightly 

 modified from R. W. Palmer). For details, see p. xl. 



angular bone is thought for various reasons to 



have served for the attachment of a pocket from 



the membranous sac that encloses the cavity of 



218 



