North America. ' 77 



tainly belongs to the true Dakota, the lower portion very proba- 

 bly extends to near the base of the Cretaceous. The evidence 

 upon which these conclusions rest will soon be published, and it 

 need only be added that the cycadean trunlss belong to this lower 

 portion though not very near the base and may not differ greatly 

 in age from those found in Southern Kansas and Maryland. 



At another part of the Black Hills region, within the foot- 

 hills on the Eastern side, some six or eight miles north of Eapid 

 City, and between that place and Piedmont, and also probably 

 in the Cretaceous area, two other specimens have been found and 

 are now at the State School of Mines at Rapid City. The where- 

 abouts of these specimens was not known at the time that I vis- 

 ited that section, but since my return Professor Jennej, ap- 

 pointed at about that time Dean of the Faculty of the State 

 School of Mines, has discovered them there and has furnished 

 me the data for tlie brief description given below, together with 

 rough drawings, and measurements, From him I learn that in 

 1877, Mr. J. M. Leedy, then of Rapid City, now residing in 

 Florida, found these specimens at the place stated, that they re- 

 mained at his ranch for some time, were then placed on exhibi- 

 tion at a fair held at Library Hall, and not being supposed to 

 have any value, were subsequently thrown out into a vacant lot, 

 where they remained until removed to the School of Mines. 

 These forms are much more cylindrical than those found in the 

 southern section, and seem without doubt to constitute a new 

 species. I have therefore named this species Gycadeoidea Jen- 

 neyana, in commemoration of Professor Jenney's great services 

 to the people of that section as well as to science in general. 



I have not seen Professor Cragin's specimens from Southern 

 Kansas, and he unfortunately did not figure them, but he stated 

 in his description that they very closely resemble the Maryland 

 specimens, of which he had obtained a photograph and had 

 learned some particulars as to size. While he thought these two 

 forms were specifically identical, it is probably best to let them 

 remain as distinct species for the present. 



All of our American forms appear to belong to the genus 

 Cycadeoidea of Buckland. None of the taller, more slender, 

 palm-like, or branching trunks, belonging to the Old World 

 genera Bucklandia and Cylindropodium, have yet been discovered 

 this side of the Atlantic. The genera Fittonia, Yatesia, and 



