FLORA OF LAKOTA OF BLACK HILLS. 317 



previously received. I was able to refer the larger part of them to species 

 already described with greater or less confidence. The residue remain 

 indeterminable. I completed this work on May 15, and prepared an 

 article embodying the results and describing the 7 additional new 

 species, one of which, however, as we have seen (see pp. 203 to 204), 

 has proved to be probably of Jurassic age and to belong to the genus 

 Cycadella. The illustrations for this article were prepared by Doctor 

 Beecher after my departure for Europe from memoranda which I fur- 

 nished before leaving. The article did not appear until November." 



In addition to the matter relating to the Jurassic of the Black Hills 

 furnished me by Mr. Wieland (see pp. 203-204), he has also sent me his 

 notes on the Lakota obtained during his investigation of the hills the 

 same season (1900). As these embody much new information relating 

 to the flora of the Lower Cretaceous of the Black Hills, I gladly insert them 

 at this place. They consist of trial sections for the study of the fossil 

 faunas and floras of the formation, with appropriate discussion, and also 

 contain the description and illustration of a new species of Nilsonia 

 collected by Mr. Wieland. 



NOTES ON THE STRATIGRAPHY AND PALEONTOLOGY OF THE BLACK HILLS RIM. 



B}- G. R. Wieland. 



The United States Geological Survey has for several years past engaged 

 actively in the field investigation of the geology of the Black Hills, a 

 region which has been recognized by all as of paramount scientific interest. 

 Hence it might seem superfluous either to add to the various sections 

 already published by Ward, Darton, and others, or in any way to anticipate 

 the more extended publications of the Survey on this subject. But as it 

 has been my good fortune to make extensive saurian and plant collections 

 in the Black HiUs rim country, and as many of these specimens are types 

 of the highest interest and come from a series of localities girdling the 

 Black Hills, my notes on the localities and horizons in which these fossils 

 were secured may well be recorded. 



It is well known that 5 or 10 vertical feet may be just as important 

 from a biologic as from a stratigraphic standpoint. Far too often 



" Elaboration of the fossil cycads in the Yale Museum, by Lester F. Ward: Am. Journ. Sci., 4th ser., Vol. X, 

 November, 1900, pp. 327-345, pi. ii-iv. 



