WHITE PINE SHALE FAUNA. 81 



course the uppermost members of the Nevada limestone. The following 

 section gives the sequence of beds from the Quaternary plain westward 

 across the White Pine shale and the underlying limestone until the beds 



are cut off by the fault. 



i ... 



1. Shaly sandstone followed by 50 foot of dark argillaceous shale and a great thickneas of 



arenaceous shale and thinly bedded sandstone ; occasional lied* of fine siliceous con- 

 glomerate ; constant changes from shale to sandstone 1,000 



2. Black argillaceous shale passing into arenaceous shale and shaly sandstone becoming dis- 



tinctly bedded and passing up into a fine siliceous conglomerate. Throughout the series 



are occasional thin belts of argillaceous shale 400 



3. Gray criuoidal limestone in layers of varying thickness and more or less sandy ; carries 



Chonetea 50 



4. Dark bluish black argillaceous and calcareous shale weathering yellow on the surface ; 



fossiliferons 300 



5. Blue limestone with alternating thin massive layers ; fossiliferous 250 



6. Siliceous limestone passing into gray limestone with irregular seams and nodules of 



calcite 150 



The lower gray limestone carries no fossils. 



In the massive blue limestone (No. 5) occur the following Upper 

 Devonian species: 



Productus shumardianus. Ehynchonella duplicate. 



Spirifera eiigelmanni. Leperditia rotundatus. 



Atrypa reticularis. Styliola flssurella. 



In the overlying 300 feet of clay shales (No. 4) the more calcareous 

 portions carry Spirifera engelmannl and Productus shumardianus, while in 

 the more argillaceous strata are numerous imperfect plant remains. 



The gray limestone (No. 3) overlying the black shale is characterized 

 by typical Devonian forms: Chonetes mucronata, Spirifera ctiijclnuinni and 

 Beyrichia occidentalis. Above this latter limestone in the clayey and sandy 

 strata (Nos. 1 and 2) no invertebrate forms have as yet been obtained, but 

 numerous fragments of plant remains, some of which would doubtless 

 admit of generic determination, are abundant. A careful search for a 

 Devonian flora would yield important results. The evidence of the 

 Devonian age of the upper 1,400 feet of shales and sands is apparent, 

 from the identity of the plants with those obtained from the black shale 

 below the gray limestone as well as from the character of the sediments. 

 Another locality where the Nevada limestone and White Pine shale are 

 MON xx (i 



