74. JOURNAL OF THE ARXOLD ARBORETUxM [vol. i 



herbarium, but lie luis also distributed among his Salic. Scand. Exsiccatae 

 under no. 118^ a photograph of '' Salix phyh'clfoUa L. originalis et ty])ica/' 

 and l^esides this under no. 11(5, 117 and 119 a-c he has distributed male and 

 female specimens of what he regards as typical plnjJiciJolia. Therefore I 

 base my judgment as to the characters of this species on Enander's speci- 

 mens and descriptions. Of the so-called American phyllcifolia I have all 

 the material before me that can, possibly, be brought together from existing 

 collections. 



In 1868, Andersson said under S. chlorophyUa: "Cum nostra S. phylici- 

 folia congruit forma et colore foliorum ut etiam habitu amentonnn sessi- 

 lium, sed diffcrt foliis pilis argenteis plus minusve dense conspersis etiam 

 denunu subdcrelictis, amentis angustioribus et cfMnjinclioribus, capsulis 

 subscssilibus, stylo multo longiore (saepe capsulae longitudine aequante et 

 filiformi). sligmatibusqueelongatis integris." He believed his var. denudata 

 to be most closely related to phyUcifolia, saying: *' Jam monui me specimina 

 Salicis a White Mountains vidisse quae nullo niodo, nisi foliis ellipticis 

 integerrimis, a nostra ^. phylicifolia rccedunt. Num hujus sjicciei forma 

 maxime denudata ?'' In 1889, IJebb, as I have already pointed out, de- 

 clared that these differences mentioned by Andersson had not been con- 

 firmed by his investigations. He had compared material from Lapland, 

 collected l)y Dr. Hankenson, which he, at first, could not distinguish from 

 specimens collected by Faxon in the White Mountains. But a few months 

 later in the same year (in Bull. Torr. Bot. CI. xvi. 211), in a note, Bebb made 

 the following statement: *' Concerning the general character of the White 

 Mountain S. phylicifolia, my remarks were miguarded and do not fairly 

 state the amount of actual divergence from the Old World type. While I do 

 not wish to qualify at least what was said of the closeness of resemblance 

 observed between some of Mr. Faxon's specimens and certain others of 

 genuine phylicifolia from Lapland, it is nevertheless true that from the 

 conunon meeting ground thus indicated, the Euroj)ean forms vary mainly 

 in the direction of S. nigricans, S. caprea, etc., whereas in this country the 

 variation is in the direction of S. chlorophyUa, and hence in so far as any 

 difference appears in a series of s])eciniens, it is a difference marked by 

 shorter pedicels, longer styles, and more slender aments. I intended my 

 closing words to cover this, but was not sufficiently explicit." I have in- 

 vestigated the Lapland material w^hich Bebb had before him. It is pre- 

 served in his herbarium in herb. C. under Nos. 11449-1145^2 from Prtca (?), 

 Gustafsho, and Skadson (?), collected at different times during 1879, 1883, 

 1885 and 188G. The difTerences are not very obvious but a careful com- 

 parison shows that these forms are distinguished by larger fruits, larger and 

 thicker fruiting aments, more distinctly crenate leaves, and especially by 

 the fact that the larger leaves point to forms different from those observed 

 in America. In my key I have tried to indicate the main differences between 

 S. phylicifolia sensu stricto and S. chlorophyUa denudata (now S. planifolia). 

 Tlie young branchlets of the American species very often show, more or less 



distinctly, a glaucous hue which never seems to be present in S. phylicifolia 



