330 



ROY L. MOODIE 



other fossil reptiles, has failed to convince me that there is any 

 advantage in such a complicated method. Sections prepared by 

 tlio ])oti-og;i-aphic method, which consists in cutting with a saw 

 and grinding with eniei'y powder on a leaden disc, are fully as 



J^ter^/ h, 



of cereJbeJJom 



tSefr?<circui&r CSTiaI-} 



Tuberculoni 



'"Ear 



Fig. 1 Brain of Rhadinichthys deani Eastman from the Mississippian of 

 Kentucky. X 10. The plane of the section is shown in the heavy transverse 

 line. This brain is almost identical in type with those from Kansas. 



useful, and so far as the photomicrographs show fully as capable 

 of exhibiting anatomical detail as the more tedious methods of 

 Lignier and Seitz. This statement is based on an examination 

 of several score of sections of fossil structures, chiefly bone, rang- 

 ing in age from the Devonian to Recent, all of which have been 

 prepared by the petrographic method. In the present instance 



