CONTENTS. 
Page. 
Letter of transmittal from Prof. Geo. H. Cook... 22. 22... 22 21 ene cen cee eee eee ne eee eee eee 9 
Letter of transmittal from Prof. R. P. Whitfield. ...... dees eens wee ee ne cee ene cee eee cence Bt 
Preliminary remarks...-.. ..- 226 2-22-22 een cee eee cee eee eee ne ee cece eee cee eee 13 
Gasteropoda ... 2. 2.222. enn ne nee eee eee cee cee cnn wn ee cone ee seen ee neee nnee sees 17 
Section I. Gasteropoda of the Lower Marl Beds.......-- - wleeeeee wa eee eens cece eee 19 
II. Gasteropoda of the Middle Marl Bed........-... -- eee eeeee tae cee w ee ceee cone 172 
III. Gasteropoda of the base of the Upper Marl Bed.........-.------------ ea eeeee 182 
IV. Gasteropoda of the Eocene Marls ........ eee cee cee ce eee cen ee cece ee eee eee 190 
Cephalopoda . 2... ..-.- 2-220 22 oe wenn ee eee nee ee ee ce ene eee ce eee teens wee ece eens . 241 
Section V. Cephalopoda of the Cretaceous Marls. ..... -.....---- ---08 eens ee eee ee eee 243 
VI. Cephalopoda of the Eocene Marls ...... ween eee cee Leese eee cece eee eee 284 
Classified lists of the Mollusca of the Cretaceous and Eocene formations.......-..---.------- 2389 
Plates... 220 2 on coe wee ce we cw ee ce cee eee eee ee cee ene cee ee ne cee eee cece ec ee ens 297 
Index. ..... 220 -eee eee eeeee eee Lene ceeeceeees Lene Snes cece eens seenee cone sone cee cone cece cere 399 
