H. Doc. 129. 29 



Great Basin. They constitute beds, with a combined thickness of 

 several feet, lying interstratified conformably with sandstone strata, 

 probably of tertiary age. These beds are almost wholly composed of 

 these stems, closely matted together and twisted in various directions. 

 The color of the fossils is very different from those on the banks of 

 Kern river, being a light blueish-grey, while the former are yellow 

 or drab. Their size is also different ; but in the appearance and char- 

 acteristics of their organization, as shown by a cross fracture, they 

 appear to be identical. It is evident that the Kern river boulder was 

 not derived from this locality, and that another deposit must exist. 



Specimens from Kern river have been ground down and polished by 

 a lapidary, and the internal structure is beautifully displayed by 

 them.* These specimens, and others from the Great Basin, were 

 submitted to Professor J. W. Bailey, of the United States Military 

 Academy at West Point, who has kindly examined them microscopi- 

 cally, and has drawn an elaborate figure showing their structure. 



The following is a copy of his letter accompanying the drawing : 



WEST POINT, New York, March 22, 1855. 



DEAR SIR : I send herewith a sketch of the structure of the fossil 

 plant from the boulder in the bed of Kern river, (west slope of the 

 Sierra Nevada.) 



The plants, as far as I can make out the structure, are annual 

 shoots of an exogenous structure, presenting a distinct pith, (p. in the 

 drawings) ; medullary rays (r) ; a layer of liber (1) ; and a 'loose 

 succulent bark (b), having large lacunas (la). In the outer portion of 

 the wood a series of large vessels, v 1 ; of smaller, v 2 ; and of still 

 smaller ones, v 3, are placed. I could not detect upon these vessels 

 any indications of spiral or dot. 



The specimens from the east slope of the Sierra agree in all essen- 

 tial points with the above, the only difference noticed being the devel- 

 opment of a few large vessels surrounded with woody fibre within the 

 pithy portion. 



I cannot venture with the limited data furnished above to form any 

 opinion upon the affinities of these plants. 



The vertical section, fig. 1, is made up from observations of various 

 splinters from different parts of the plants which I encased in Canada 

 balsam. The horizontal section, fig. 2, is from the section made by 

 the lapidary in New York, which I afterwards rubbed down to half 

 the thickness the lapidary tad given. The section thus obtained was 

 as perfect as if from a recent plant. It showed the cells filled with 

 transparent silica, and in the larger lacunas the arrangement of the- 

 silica into small spherical agates was distinctly visible. 

 Yours, very respectfully, 



J. W. BAILEY. 



W. P. BLAKE, Esq., Washington, D. C. 



* Several other sections of these fossils are being prepared, and the results of their examin 

 ation will be presented in the final report. 



