U. S. G. AND G. SURVEY. 



PREHISTORIC TREJ'JIINING, PI. I'. 



Cranium from CilKHU'nioa. A-B, median line ; E, left external orbital apophysis ; F, rightcstemalorbitalapopbysis, 

 broken, a-b, tbe cicatrized edge of surgical trephining ; a-c, h~d, post-mortem sections. The sagittal suture, iust«ad of 

 following tbe line C-D, has been driven over to tbe left. Two-thirds natural size. (Broca.) 



