i">2 Rhodora [February 



A pubescent Form of Salix Uva-UBSI. — The common matted 

 willow, Salix Uva-ursi Pursh, of the granitic alpine summits of 

 northern New England, the Adirondack^, and the region northward 

 to Labrador has its small crowded leaves quite glabrous, glaucous 

 beneath hut dark green and lustrous above; so that the hearherry- 

 like carpets make conspicuous glistening mats on the mountain crests. 

 In the White Mountain region the shrub abounds on the Presidential 

 and Pranconia Ranges and is generally quite typical; hut near the 

 base of the western spur of Mt. Lincoln are considerable carpets which 

 at once arrest the attention by their dull whitish color. Examination 

 shows that in these colonies the foliage, instead of being glabrous, is 

 canescent with a close somewhat arachnoid but persistent pubescence. 

 In this character the puhescent shrub of Mt. Lincoln simulates some 

 of the Arctic-alpine species of Gaspe, Newfoundland and Labrador, 

 S. curd i folia Pursh for instance, hut in all other characters it seems to 

 be pure S. Uva-wrri; and the beautifully definite key -character, of 

 glabrous foliage, which has so long separated it from some other spe- 

 cies of the North now unfortunately becomes weakened. This 

 extreme form may he called 



Salix Uva-URSI Pursh, forma lasiophylla. n. f., foliis puhesccn- 

 tibus, pilis canescentibus plus minusve arachnoideis. 



Leaves with more or less arachnoid canescent pubescence. — New 

 HAMPSHIRE: granitic gravel and peaty slopes, western spur of Mt. 

 Lincoln, Pranconia, August 11, 1915, Fernald, no. 11,665 (type in 

 Gray Herb.). — M. L. Fernald. 



Vol. IS, no. 20o, including pages 1 to 28 and plates ll/ t to 117, was issued ill 



January, I!) 16. 



