WHITE PINE SUALE FAU^'A. 81 



course the uppermost inenibers of the Nevada limestone. Tlie t'oUowiui^ 

 section gives the sequence of beds from tlie (^uatcniarv pUxiu westward 

 across the White Pine shale and the uuderl\'iuL;- limestone until the beds 

 are cut off by the fault. 



Feet. 



1. Shaly sanilstone followed Wy ."lO fccl of ilaik ar^illaci-oii.s shalv ami a griMt lliirkiu-.ss of 



areuari'oii.s .shale and thinly hedded sandstone ; oecasional l)ed.s of line silieeons con- 

 glomerate ; constant changes from shale to sandstone 1 (XX) 



2. Black argillaceous shale pa-ssing into arenaceous shale and slialy sandstone heiuimiu"' dis- 



tinctly bedded and passing up into a fine siliceous conglom<'rate. Throughout the series 



are oecasional thin belts of argillaceous shale 400 



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



Chonete* 50 



4. Dark blui.sh black argillaceous and calcareous shall- weathering yellow on the surface ; 



fossiliferous 300 



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



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



calclte 150 



The lower gray limestone carries no fossils. 



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

 Devonian species: 



Productiis shuinaidianus. Khyncliouella tluplicata. 



Sphifera engeluiaimi. Leperditia rotundatus. 



Atrj-pa reticularis. Styliola flssurella. 



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

 portions carry Spirifera enf/elmaniii and Proihidns slmmanlianus, 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: Cltonrtcs miuroimta, Spirifera oifjchiianni and 

 Beyrichia occidentaUs. Above this latter limestone in the clavev and sandy 

 strata (Nos. 1 and '!) no invertebrate forms have as yet been olnaiiied, but 

 numerous fragments of plant remains, some of Avhich would doubtless 

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

 Devonian tlora would yield important results. The evidence of the 

 Devonian age of tlu^ upi)er 1,400 feet of shales and sands is apparent, 

 from the identity of tlu^ 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 G 



