166 



University of California Publications in Geology [Vol. 9 



and a summary of available information regarding the fauna and 

 flora of the Esmeralda. 



In the type section of the Esmeralda, Turner describes the for- 

 mation as consisting of light-colored marls, shales and sandstones, 

 water-worn conglomerates, and Tertiary detrital-slope breccias. The 

 formation was considered to have a thickness of at least 10,000 feet, 

 and was presumed to represent in large part accumulation in a fresh 

 or only slightly saline lake. Remains of plants, fresh-water molluscs, 

 and fish indicated that the beds represented approximately Miocene 

 age. 



An interesting succession of lavas described by Turner from the 

 Silver Peak region has definite relation to the Esmeralda sedimentary 

 series and is therefore of unusual importance. The succession is as 

 follows, reading from the latest members to the earliest ones referred 

 to the Tertiary : 



7. Dark, fine-grained olivine basalt, which may not be later than the Piper 



Peak flow. 

 6. Hypersthene basalt of Piper Peak. 



5. Rhyolite-tuff interbedded with sandstones of the Esmeralda formation. 

 4. Andesite-breccia. 

 3. Rhyolite-tuff. 

 2. Andesite-breccia. 



1. Older basalt associated with red basal conglomerate of the Esmeralda 

 formation. 



The plants of the Esmeralda were examined by F. H. Knowlton 5 

 who listed the following forms : 



Quercus turneri Knowlton 



Dr. Knowlton considered the flora of comparatively recent age 

 with some species having closely corresponding forms as old as Eocene. 



Tree trunks six to eight feet in diameter were found in the Esmer- 

 alda beds by Turner. 



The fish remains were described by Dr. F. A. Lucas' 1 who referred 

 them to a new species of the cyprinoid genus Leuciscus. This form, 



•-■ Knowlton, F. H., U. S. Geol. Surv. 21st Ann. Rep. part II, pp. 209-224, 1900. 

 o Lucas, F. A., U. S. Geol. Surv. 21st Ann. Rep. part II, p. 223, 1900. 



Gleichenia ? obscura Knowlton 

 Dryopteris? gleichenoides Knowlton 

 Spathyema? nevadensis Knowlton 

 Salix angusta? Al. Br. 

 Salix vaccinifolia Knowlton 

 Salix, sp. 

 Salix?, sp. 



Quercus argentum Knowlton 

 Fieus lacustris Knowlton 

 Chrysobalanus pollardiana Knowlton 

 Cercis? nevadensis Knowlton 

 Cinchonidium? turneri Knowlton 

 Elms nevadensis Knowlton 

 Indet. 



