30 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Ser. 



TURRITELLA PORTERENSIS ZONE 



The type locality at which this fauna may be found is 

 located in the cliffs along the north bank of Chehalis River 

 near the mouth of Porter Creek, in Chehalis County. Ex- 

 posures of the same strata also occur in the banks of the 

 small creeks entering Chehalis River from the north in the 

 vicinity of Porter Creek. The most common species appear- 

 ing in this zone are Cardium lorenzamim Arnold, Crenella por- 

 ter ensis Weaver, Malletia chehalisensis Arnold, Marcia ore- 

 goneusis (Conrad), Thracia trapesoidea Conrad, Thyasira bi- 

 secta (Conrad), Phacoides acutilineatiis (Conrad), Drillia he- 

 coxi (Arnold) and Turritdla porterensis Weaver. Such spe- 

 cies as Acila gettyshiirgensis Reagan, Macrocallista vespertina 

 (Conrad), Modiolus directus Dall, Panope generosa (Gould), 

 Eudolium pctrosmn (Conrad), Titrcicula zmshingtoniana 

 Dall and Turritdla blakeleyensis Weaver are absent. These 

 species are, however, among the most characteristic occurring 

 in the Acila gettysburgensis zone. It is possible that the Tur- 

 ritdla porterensis zone may be represented beneath the lower- 

 most beds of the Acila gettysburgensis zone south of Orchard 

 Point at the Bremerton Inlet section. If so, it occurs be- 

 tween the lowest conglomerate belt of the Acila gettysburg- 

 ensis zone and the underlying Eocene basalts near Port Or- 

 chard. This region is covered with glacial drift. The lower 

 beds in the Clallam County area as exposed three miles west 

 of Port Crescent may also represent this horizon. 



ACILA GETTYSBURGENSIS ZONE 



The type locality where this fauna may be found is in the 

 sea cliffs about the entrance to the Bremerton Navy Yard. 

 The lowermost strata occur at Orchard Point. The highest 

 strata outcrop along the north shore of the entrance to Blakeley 

 Harbor. The total thickness of the beds here exposed is 8,900 

 feet. Detailed stratigraphic surveys show that the conglom- 

 erates at Orchard Point are below the sandstones and shales 

 at Bean Point. The beds at Bean Point are about 2,000 feet 

 below the fossil iferous beds at Restoration Point. The fauna 



