346 ROY L. MOODIE 
The Pleistocene mammals are represented by a partial brain 
case of Smilodon from the Pleistocene deposits of the Rancho la 
Brea of southern California, and a complete brain case of Aeno- 
cyon dirus, the giant wolf of the same beds. In order that 
accurate casts might be made, the task of removing the bitumen 
and taking correct impressions of the rugose endocranial cavities 
was entrusted to Mr. Adolph Hammer, director of the plastic 
studios of the department of anatomy. His success will be evi- 
dent from the figures of these casts (figs. 13 to 16) made by 
Miss Genevieve Meakin, artist in the department. Comparisons 
have been made not only with figures of other casts, but with 
artificial casts of modern mammals. All the material used in this 
study will be deposited with the Walker Museum at the Uni- 
versity of Chicago. 
DESCRIPTION OF ENDOCRANIAL CASTS 
The casts are all in fairly good state of preservation, though 
they have suffered the accidents to which all fossils are subject, 
being cracked, broken, and weathered. While these accidents 
have obscured certain of the anatomical features, especially of 
the olfactory bulb and cerebellum, yet sufficient remains to 
justify description. Photographs of the casts have not been 
made, since half-tone reproduction usually destroys the greater 
part of the detail. 
Measurements of each cast have been made on the basis out- 
lined by Black (’20) and his terminology has been adopted. The 
displacement of the objects had been obtained by immersing 
them in a large graduate partially filled with water. While this 
method does not give an accurate conception of the endocranial 
capacity of each mammal, since the casts are often incomplete, 
yet the capacity is so closely indicated that it is worth recording. 
The fine work of Bolk (06) has been depended upon for 
identification of parts of the cerebellum where such was possible 
and the extremely useful catalogue compiled by G. Elliot Smith 
(02) has been the guide in the interpretation of parts of the 
cerebrum. Particular reference is not made to the many general 
comparative anatomies consulted, such as Gegenbaur, Sisson, 
