1907] BRIEFER ARTICLES 281 
ment, I do not believe it to be entirely so, and suspect that in cultivation 
they would remain distinct, age for age, B. papyrijera growing more 
rapidly.” 
Further studies another season may show other characters that will 
absolutely separate this newly found birch from B. papyrifera. Should 
such be the case, the writer will then propose the name Betula Andrewsii 
for this new find, in honor of Mr. ANDREws, whose diligent studies and 
discriminating observations in the field are again recognized—studies the 
more valuable because the opinions formed in the field are usually verified 
in his experimental and nursery grounds at Boulder—AveN NELSON, 
University of Wyoming, Laramie. 
RHODODENDRON ALBIFLORUM WITH DOUBLE FLOWERS 
While on a botanizing tour with Mr. J. G. Jack in British Columbia 
in the summer of 1904, we were staying several days at Glacier, the station 
of the Canadian Pacific R. R. close to the foot of the Great Glacier of the 
Selkirks, to explore the surrounding country. Just above the hotel in the 
Asulkan valley there is a grove of Tsuga Mertensiana and T. heterophylla, 
through which a path leads to the foot of the glacier. As I left this path 
to cross a thicket of small hemlocks to the bank of the Asulkan River, 
I noticed close to the brink of the river a large shrub of Rhododendron albi- 
florum in full bloom which at once attracted my attention, as all other 
shrubs of this species were past flowering; and I was very much astonished 
to find on coming nearer that it bore large white double flowers very much 
like those of the double cherries sometimes cultivated in gardens. It 
was a strange sight in these wild and rough mountain woods to see such 
blossoms which one associates involuntarily with the finished surroundings 
of a well-kept garden. What agency caused the origin of such a form? 
Close by grew the typical form, and there was nothing unusual in the place 
or position where the shrub grew, nor in the shrub itself aside from its 
double flowers. This is probably the first time that a double-flowered 
Rhododendron has been found in this country. Though reports of the 
occurrence of double-flowered plants in a wild state are not wholly lacking, 
they are nevertheless rare. In the European Alps Rhododendron jerrugi- 
neum has been found at least twice with double flowers, as reported by A. 
KERNER (Oesterr. Bot. Zeits. 15:285. 1865), who himself found in one 
locality a large number of shrubs with double flowers. 
As in most double flowers, the cause of this teratological aberration is 
in this case petalody of stamens combined with a considerable increase 
