1915] Farwell,— The Hemlock Spruce 165 
not been specifically mentioned or designated, the first author revising 
the species must of necessity make his own choice as to which element 
shall bear the name. That choice should be, and perhaps is, generally, 
determined by the internal evidence. 
Mr. Rehder fails to see wherein my reference to Article 46 of the 
Vienna Rules bears upon the case at issue since the Article mentioned 
treats of the combining of two or more species and not of the division 
of one. The Vienna Rules are general laws for the guidance of such 
botanists as have subscribed to them. In the treatment of species, 
the first author revising them is given, under certain conditions, the 
choice of making his own interpretation as to the application of the 
specific names and subsequent revisers cannot alter this interpretation. 
The Vienna Congress in handling this subject relating to the treatment 
of species first considers the combining of species and it is here that 
the general law making the author’s choice of name, under certain 
conditions, permanent, is expressed. When considering the division 
of a species, the Congress, acting upon the basis that “brevity is the 
soul of wit," declined, and justly so, to perpetrate a needless repetition. 
In regard to the detailed description of Pinus Balsamea Linnaeus, 
which Mr. Rehder fails to see is not restrictive, it may be remarked 
that the leaves of Tsuga caroliniana, a species growing in Virginia, 
may be notched at the end, thus coming under the designation sub- 
emarginatis. Also that the leaves of A. Fraseri may be either emargi- 
nate or obtuse. Rehder claims that it had not been discovered at the 
time P. Balsamea was published. It would be more accurate to say 
that it was not recognized at the time as a distinct species but there 
is no evidence to prove that it was not known and included in Pinus 
Balsamea. It must therefore be considered in any discussion of the 
subject. The leaves of the Balsam Fir from Vermont show an 
emarginate apex but those from the Lake Superior district have no 
such markings but are as rounded and as obtuse as the leaves of the 
Hemlock. The leaves of the Hemlock Spruce are as broad as those of 
the Balsam Fir so they are not excluded from consideration by a com- 
parison of the latter with those of the Silver Fir. The white bands 
on the under side of the leaves in the Hemlock are usually composed 
of four rows of stomata but frequently are of five or six and sometimes 
of seven or eight; those on leaves of the Balsam Fir of Lake Superior 
are generally of seven or eight rows but are frequently of any number 
between four and eight inclusive while those on trees from Vermont 
