678 GEOLOGY OF THE YELLOWSTONE NATIONAL PARK. 



closed on this account, or is a strictly serotinous form, is a difficult matter 

 to decide. On the whole it seems probable that it was nearly or quite 

 mature, and should be placed among those with normally closed scales. 



The next question is, What is the age of this cone? — that is, is it a 

 cone of a recent species or does it represent an extinct form? The phe- 

 nomena are so active in the Park at the present time that it is perhaps 

 possible for a cone of this kind to be replaced with silica within a com- 

 paratively short space of time. It however came from a part of the Park 

 where the hot-springs phenomena have ceased for a long period, and this 

 lends color to the idea that it is not of very recent origin. The probability 

 is, therefore, that it represents an extinct rather than a living' species. 



This cone clearly belongs to the pitch pines and not to the soft or white 

 pines, and in determining its affinities this latter group must be excluded. 

 At the present time there are 3 species of pines growing in the Yellow- 

 stone National Park, as follows: Pinus scopulorum, P. flexilis, and P. contorta 

 murrayana. Of these, P. flexilis belongs to the white pines and the others 

 to the so-called pitch pines, and of these the last, or P. contorta murrayana, 

 is by far the most abundant. 



I have shown this cone to a number of botanists familiar with the 

 present flora, and there seems to be much diversity of opinion as to its 

 probable relationship. Mr. F. V. Coville, botanist of the Department of 

 Agriculture, inclines to regard it as allied to an immature cone of P. scopu- 

 lorum, but a careful comparison fails to sustain this view. Mr. George B. 

 Sudworth, dendrologist of the Department of Agriculture, regards it as 

 most closely allied to P. contorta murrayana, the lodge-pole pine, and I have 

 so considered it. It is of approximately the same shape as mature cones of 

 this species, but is longer and rather narrower. It is not improbable, as 

 suggested by Mr. Sudworth, that it represents a form which was the imme- 

 diate ancestor of P. contorta murrayana, and I have given it the tentative 

 name of premurrayana. 



Habitat: East of the Yellowstone Lake, Yellowstone National Park. 

 Collected by members of the Yellowstone National Park division of the 

 United States Geological Survey. 



Pinus 



sp. 



Cone lanceolate?, about 16 mm. in diameter, length of part preserved 

 18 mm.; scales 5 rows in part preserved, probably about 10 or 12 in 



