90 GEOLOGY OF THE EUREKA DISTRICT. 



Sanguinolites naeuia. Euomphalus subrugosus. 



Sanguinolites retusus. Pleurotomaria nodomarginata. 



Sanguinolites salteri. Bellerophon textilis. 



Sanguinolites simplex. Naticopsis, sp. ? 



Sanguinolites striata. Dentalium, sp. f 



Microdon connatus. Orthoceras randolphensis. 



Schizodus cuneatus. Ortboceras, sp. ? 



Schizodus deparcus. Gomphoceras, sp. ? 



Cardiola filicostata. Griffithides portlocki. 



Below this horizon there is a bed of bluish gray limestone interesting 

 on account of its grouping of Lower Coal-measure fossils without the 

 presence of any of those species which might be regarded as indicating a 

 lower stratigraphical position, but which are here found in the overlying 

 strata. The list is small, but characteristic of the Coal-measures. It is as 

 follows : 



Fenestella, sp. f Productus semireticulatus. 



Streptorhynchus crenistria. Spirifera camerata. 



Chonetes granulifera. Rhynchonella eurekensis. 



Productus prattenianus. Griffithides portlocki. 



Richmond Mountain Fauna. There is some reason to believe that the inter- 

 calated arenaceous and calcareous strata lying at the base of the great 

 limestone belt all the way from Richmond Mountain southward to Fish 

 Creek Valley represents a portion of the chocolate-colored clay shales 

 underlying the limestone of Diamond Peak, and referred to the upper 

 members of the Diamond Peak quartzite. From the base of the Lower 

 Coal-measure limestone along the Hoosac fault up to the capping of 

 andesite lavas of Richmond Mountain the highly inclined strata measure 

 about 1,800 feet. Fossils occur scattered throughout the limestones. From 

 highly fossiliferous strata favorable for their preservation, a grouping of 

 species was found which may be taken as typical of the entire epoch, 

 although only in a few localities is the life so full and well represented. 

 This list from the southwest base of Richmond Mountain is as follows : 



Zaphrentis. Streptorhynchus crenistria. 



Fenestella, sp. t Chonetes granulifera. 



Lingula mytaloides. Productus longispinus. 



Discina newberryi. Productus nebrascensis. 



