4 PLANTS BAKERIASLE. 



some authors) attains the height of eight or ten feet; but up 

 near the timber-line it is a dwarf of sometimes not more 

 than one or two feet. The more conspicuous herbaceous 

 plants of these thickets are Mertensia ciliata, Geranium Rich- 

 ardsonii, a new species of buttercup, Ranunculus Earlei 

 (Greene), and Polemonlum filicinum, a species originally from 

 southern New Mexico, and which here it may be assumed, 

 reaches its northern limit of distribution. Among such as 

 these were also gathered a few herbaceous plants, notably 

 Carex aurea and Collomia lanceolata, and several more, which 

 are more properly subalpine and alpine. And as we after- 

 wards grew familiar with the whole region, including the 

 higher elevations about the headwaters of this stream less 

 than twenty miles away, the wonder constantly grew, not 

 that only a few alpine or subalpine plants should occur in 

 the valley below, but that so few of these species had been 

 able to adapt themselves to the condition of the lower levels 

 even where the cool thickets furnished such excellent shade 

 with abundant moisture, and the rapidly flowing stream 

 offered such abundant facilities for the downward distribution 

 of seeds. As a rule the Mancos specimens of species having 

 a considerable altitudinal distribution were taller and more 

 slender than those subsequently taken in mountain mea- 

 dows ; which variation seems attributable partly, at least, to 

 their having grown in the shade. But in other cases, such 

 as the Collomia and Carex aureo,, the low elevation seemed 

 to have had the opposite effect of dwarfing the plants ; speci- 

 mens from about Mancos being much smaller than those 

 taken at elevations greater by a thousand feet. 



Separated from the flood-plain by a steep bank five to fif- 

 teen or even twenty feet high, and constituting a more 

 elevated secondary bottom, the sage plain stretches away 

 for a mile or more on either side of the valley to the foot- 



