130 BOTANICAL GAZETTE [AUGUST 
there to get a correct conception of the relationship of those arctic 
forms. I am not fully convinced that the presence of stomata in 
the leaf surface of S. anglorum and their absence in S. arctica typica 
can be regarded as a decisive character in distinguishing certain 
similar forms, but I think this specific character is of great taxo- 
nomic value at least in several species. A. and E.-C. Camus lay 
much stress upon this character in establishing their systematic 
arrangement according to anatomical features, and an excellent 
observer like the well known dendrologist E. KOEHNE was always 
inclined to pay much attention to those characters. In studying 
willows we should bear in mind the following remarks of the dis- 
tinguished English salicologist, F. BUCHANAN WHITE (Jour. Linn. 
Soc. 27:346 [Rev. Brit. Willows]. 1890): 
Whilst all the parts of the plant are variable, some characters, on which 
a great deal of reliance has been placed, are so inconstant that they may, in 
many cases at least, be almost or quite ignored, though in other instances they 
are really of importance. Familiarity with the species can alone teach the 
student what are the points on which he can depend. 
At present it is impossible to interpret properly certain forms 
because we do not yet know the degree of variation of the species 
in question. There are, I am convinced, many hybrids, and the 
fact that has been recognized by all the leading salicologists in 
Europe “that willows hybridize with the greatest facility adds,” 
as WHITE (loc. cit., p. 340) says, “immeasurably to the intricacies 
of the study.” Here in America we are only just beginning to get 
a better understanding of the taxonomy, variation, and distribution 
of the numerous willows, and everyone who attempts to further our 
_knowledge of them ought to be lenient in his criticism of those 
interested in this study. 
It is not without hesitation that I propose the following varieties 
of S. anglorum, but I am encouraged by the fact that such a keen 
observer as Professor M. L. FERNALD, who has collected most of 
the material of the new forms and to whom I wish to express My 
gratitude, agrees with my treatment of them. 
S. ANGLORUM var. kophophylla,* nov. var.—Frutex prostratus 
ramis subterraneis ad ultra 1 cm. crassis, ramulis repentibus pl. m. 
4 The name is derived from xw¢és, blunt. 
