FAUISTA OF YAHOO 0A^"Y02^!. .S3 



I'nxhirfiis liirsitfifoniic iind CoJmhis /(cris. Plant remaius occur here sim- 

 ilar to those t'oiind east of 8ui>ar Loaf, hut still less perfectly preserved. 

 The identificfitiou of the Hora from the former lucalitv places the age of 

 these beds without (hiubt at the top of the Devonian, in accordance with 

 their stratigraphical position. The corresponding- horizon at White Pine 

 Mountain i)re.sents still stronger exadeuce of the Devonian age of the 

 shale; but here, as well as at Eureka, little has been accomplished by 

 investigating this ancient flora. 



Passing to the Piiion Range and the Mahogan\- Hills in tlie northwest 

 corner of the district, the Upper Devonian limestone is well exposed in 

 massive beds lying beneath the Diamond Peak ([uartzite. It is easily deter- 

 mined by its lithological habit and fauna, as well as 1)\- its geological 

 position beneath the Carboniferous quartzite. Fossils are known in a num- 

 ber of places, but the locaHties which have furnished the largest and most 

 varied fiiuna and offer the most promising return are found on the isist side 

 of Yahoo Canyon and north side of The Gate. Near the entrance to 

 Yahoo Canyon the beds have yielded a rich fauna characterized by silici- 

 fied corals. The grouping here is as follows: 



Strouiatopora. Fachypliyllum woodruaui. 



Alveolites rockfunlensis. Spirifera jilabra, var. uevadensis. 



Cladopora imlclua. Spirifera disjuiu-ta. 



Syriugopora hisiugeri. Atryi)a rectienlans. 



Syring()]K)ra iierelegaas. Rhynchouella castauea. 



Cyathopliylluui coriiiculum. ? Styliola tissurella. 



On the north side of The Gate, at a little higher horizon and directly 

 beneath the (juartzite, there is exjjosed a fine section, 500 feet in thickness, 

 of massive blue limestone, passing into shaly beds, in places almost fissile. 

 Fossils characteristic of the Upper Devonian are abundant throughout the 

 beds. The limestone vielded the following species: 



Stroinatopora. Orthis tidlieiisis. 



SjTiiigopora liisiageri. Productiis lacbrjnnosa, var. lima. 



Syringopora jjerelegaiis. Productus scliuinardiaiius. 



Cyatliophyllum coruiculinu. Prodnctns speciosus. 



Disciiia iniiiiita. Productus stigmatus. 



Orthis impressa. Productus subaculeatus. 



