OUR FACE FROM FISH TO MAN 



fishes had been replaced by two large bones hence- 

 forth traceable directly to the nasal bones of man. 

 The several bony plates on the face surrounding 

 the eye had also been changed in proportions. 



Tnara^inccl ^u/a/s- 



Fig. 17. Skulls of Lobe-finned Fish (A) and Early Amphibian 



(B), Showing Loss of Opercular Series in the Latter 



(A, after Traquair and Watson, B, after Watson). 



In the primitive amphibians the space formerly covered by the 

 opercuhar region was covered by the tympanum or drum membrane. 

 For details, see p. xv. 



30 



