OLDKK POTOMAC OK V IK* I IMA AND MAUYLAND. 555 



:J. In 1895 (the month not staUnl on llie hilx'l) Mr. Bil)l)ins collected 4 more 

 of the cones, also for the Woman's Collejre. 



4. Five si)ecimens were collected hy Mr. Bihhinsfor the Maryland State Geoloo;!- 

 cal Survey, hearing the numbers of that survey, SS7I), SS7o-SS7(). The first of these 

 bears also the date, 1S!)5. The resti have no date, but are uniform with this in all 

 other respects, and were probably obtained at the same time. 



.'). On ,Vu«i;ust 81, 189(), Mr. Bibbins and Proi'esst)r Ward made collections at 

 several points in this region, and 8 determinable specimens were collected on the 

 south side of the hill. It was near here, at a little higher leveh that the sanu' 

 party obtained on March 29, 1N94, a nearly erect trunk which was silicified in the 

 interior above and lignitized on the exterior, while the lower end consisted entirely 

 of lignite and had been used in part for fuel. 



The iron rock at this locality, lik(> the ferruginous saiui rock of the 

 Tiptop mines above described, is sand impregnated with limonite so as 

 to foi-m a pretty firm rock. The material ):)eing coarse and without 

 cleavage is not suited for the preservation of fossil plants, and at the 

 same time the plants seem to have been floated for some distance and 

 roughly used. For these reasons the impressions are those of small 

 fragments that are in general not distinct. The conditions under which 

 they have been preserved have probaljl}' acted to exclude all forms that 

 are easily destroyed, and hence the species are fewer than they would 

 otherwise be and there is a great predominance of such as could endure. 



Some of the specimens can not be determined, but there are others 

 which can be made out. The following are all the species that can be 

 determined from Soper Hall, with the number of specimens of each : 



Athrotaxopsis cxpansa Font. * 8 specimens. 



Sequoia ambigua Heer 21 specimens. 



Sphenolepidium dentifolium Font. ? 1 si)ecimen. 



Sphcnolepidium Stembergianum densifolium Font- T) specimens. 



Sequoia ambkua Ileer." 

 PI. CX, Fig. 13. 

 The most important fossils are cones in the form of mud casts, 21 of 

 which were found. These include all the cones of the first, second, and 

 third collections described above. They are more or less distorted, and 

 the plant matter had evidently in part been removed before the mud 

 took the casts. These cones are decidedly larger than the cones of 



« See p. 2G4. 



