Vol. VI] WEAVER— POST-EOCENE OF WESTERN WASHINGTON 29 



Gasteropoda Drillia hecoxi (Arnold) 



Ampullina, new species Lunatia cowlitzensis Dickerson 



Brachysphingus clarki Weaver Scaphander oregonensis Dall 



Bittium lincolnensis Weaver Surcula lincolnensis Weaver 



Cancellaria, new species Strepsidnra oregonensis Dall 



Calyptrcsa zvashingtonensis '^ trepsidura hncolnensis 



Weaver Weaver 



Drillia staiifordensis (Arnold) Molopophorus lincolnensis 

 Exilia dickersoni Weaver Weaver 



Hemifususzvashingtoniana Turritella neivcombi Merriam 



Weaver 



The above listed fauna seems to have a closer affinity with 

 that occurring at Porter Bluffs, about 20 miles to the west in 

 Chehalis County, and designated in this report as the Turri- 

 tella porterensis zone, than to the underlying Eocene. The 

 most important species which occur in common are Cardiwn 

 lorenzammi Arnold, Crenella porterensis Weaver, Dentalium 

 conradi Dall, Drillia hecoxi (Arnold), Lunatia cozvlitsensis 

 Dickerson, and Malletia chehalisensis Arnold. 



Marcia oregonensis Conrad, Thyasira bisecta (Conrad), 

 Thracia trapesoidea Conrad, and Phacoides acutilineatus 

 (Conrad) are entirely absent from the Molopophorus lincoln- 

 ensis zone. They are, however, among the most common spe- 

 cies to be found in the Turritella porterensis and Acila gettys- 

 burgensis zones. 



The following species are most characteristic of the Molo- 

 pophorus lincolnensis zone : Cardium lorensanum Arnold, 

 Crassatellites washingtoniana Weaver, Leda uvasana Dicker- 

 son, MacrocaUista piitshurgensis Dall, Fitaria dalli Weaver, 

 Brachysphingus clarki Weaver, Exilia dickersoni Weaver, 

 Lunatia cowlitsensis Dickerson, Drillia hecoxi (Arnold) and 

 Strepsidnra oregonensis Dall. 



A study of the faunas above listed indicates clearly a 

 marked distinction between the Tejon fauna proper and the 

 Molopophorus lincolnensis zone. A closer relation exists be- 

 tween the latter and the Turritella porterensis zone, although 

 there are sufficient distinctions to warrant considering them 

 separate faunal zones. 



