PLATE 40. 



CARCHARIDAE. 



Fig. 1-3. ScAPANORHYNCHUs owsTONi. M. C. Z. 1048 (Page 28). 



1. Brain from above. 



2. Brain from the side. 



3. Brain from below. 



Comparison of tlie brain of thi.s spocie.s with that of Carcharias laurua, Plate 41, proves that Scapano- 

 rhynehus is the more ijrimitive of the two genera and conversely that Carcharias is nuioh the more ad- 

 vanced. 



