256 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Se«. 



the Hemphill conchological catalogue is almost completed. Approximately 

 one-half of the Henry Hemphill conchological collection is unpacked, num- 

 bered and placed in drawer cases or exhibition cases. But little work has 

 been attempted on the excellent collections of rocks and minerals obtained 

 from the Exposition. 



RESEARCH 



During the first three weeks of June, the assistant curator investigated 

 the Eocene and Cretaceous in the Simi Hills, which are 30 miles north- 

 west of Los Angeles. Lower Eocene fossils of the Los Angeles basin ex- 

 hibit the same peculiar facies as the Martinez fauna of the San Francisco 

 basin. The abundance and variety of Turritellas, the Volutidae, the Cyp- 

 raeidae, and other tropical and semi-tropical forms, in comparison with the 

 fauna of the San Francisco basin, are evidences yielded by these collections 

 that apparently well-marked climatic zones existed during lower Eocene 

 time, in marked contrast with the vague and indefinite climatic conditions 

 of the Upper Eocene, Tejon, during which semi-tropical conditions existed 

 far north of the Equator. Palms and other tropical or semi-tropical forms 

 of the land flora occur in Washington while semi-tropical invertebrate 

 shells are numerous in the Cowlitz phase of Washington. 



Both the Rimella simplex zone or middle Tejon, and the Siphonalia 

 sutterensis zone of the uppermost Tejon, were recognized in the vicinity 

 of the Simi Hills. About five miles north of Chatsworth Pass, Mr. R. G. 

 Stoner discovered an interesting locality which yielded numerous species 

 characteristic of the uppermost Eocene of California, the Siphonalia sutter- 

 ensis zone. This zone typically occurs in the Marysville Buttes, Sacramento 

 Valley, and also extends along the western border of the Sierra Nevada, 

 the marine equivalent of the land-laid auriferous gravels. This is the first 

 recognition in California of the Siphonalia sutterensis zone in the outer 

 Coast Ranges. Presumably, in most places in the coast ranges, the upper- 

 most Eocene was removed during the interval of emergence between the 

 Eocene and Oligocene on the Pacific Coast. About 15 new species from the 

 Martinez-Eocene and about 12 forms new to science were found in the 

 Tejon Eocene in this area. 



The Marysville Buttes were visited in April by the assistant curator. 

 Eight different collections were obtained from the uppermost Eocene of 

 this region. Ten beautiful new species were found. Knoxville cretaceous 

 fossils were discovered for the first time in this ancient volcano of the 

 Sacramento Valley. The uppermost Cretaceous, Chico group, was dis- 

 covered in four different localities and fair collections were obtained. No 

 Horsetown or middle Cretaceous was found in this area; presumably an 

 interval of erosion in this region represents Horsetown time, as these de- 

 posits occur in great thicknesses 30 miles west of the site of the Marys- 

 ville Buttes, or faulting has uplifted the lower Cretaceous — the Knoxville— 

 and lowered the upper Cretaceous, the Chico, and concealed the middle or 

 Horsetown member of this Mesozoic period. 



During three weeks in July, the assistant curator, aided by Mr. John B. 

 Kerr, collected from seven dififerent localities in the Merced formation. 



