76 Ward Fossil Cycadean Trunks of 



of the Rocky Mountains, and Cretaceous and Jurassic strata un 

 doubtedly crop out immediately above this locality. 



Early in the spring of 1893, the National Museum obtained 

 possession of a collection of six fine cycadean trunks from 

 parties residing at Hot Springs, South Dakota, who had collected 

 them at that vicinity.* One of these specimens measures thirty- 

 one inches in height and twenty-four in greatest diameter, and 

 weighs nine hundred pounds ; the others are comparatively 

 smaller, the smallest of all not exceeding a foot in height. Most 

 of them are considerably flattened, but one or two are nearly cir 

 cular in cross section. One of them exhibits a number of lateral 

 branches, and in most cases the apex is depressed, forming the 

 "crows nests" so characteristic of the specimens from the Isle of 

 Portland, Dorsetshire, England. 



In the Geology of the Black Hills, prepared by Profes 

 sors Newton '-and Jenney, from their survey of 1875, and 

 published at Washington in 1880, none of the Cretaceous 

 strata below the Dakota group of Meek and Hayden, are 

 recognized; and while I presumed from the general his 

 tory of this class of vegetation that these remains came out 

 of the Triassic Red Beds, or the overlying Jurassic, I was still 

 so greatly interested to ascertain their true source that early in 

 September last I made an expedition to the region, and in coop 

 eration with Professor Jenney discovered the locality and made 

 further collections, including one very much branching and- 

 very large trunk and many interesting fragments. All the re 

 mains of this class that have been thus far found in the southern 

 part of the Black Hills, occur in the area mapped as Dakota 

 group by Professor Newton, and, although no cycadean vege 

 tation had yet been found amidst the extensive collections from 

 the Dakota group of Kansas, Nebraska, and other more eastern 

 localities, we were at first disposed to accept this as proof of their 

 occurrence at that horizon in this region. But the great im 

 probability of this assumption led us to make a careful examina 

 tion of the series that had been thus classed by Professor New 

 ton. The result was that we came to the conclusion that the 

 Dakota group of Newton is much more extensive than the No. 1 

 of Meek and Hayden, and while the upper portion of it cer- 



*See Science, Vol. XXI, New York, June 30, 1893, p. 355. 



