1919] Farwell,— Final Word on Tsuga americana 109 
technical description from Linnaeus; also that if the word submembrana- 
ceis excludes the White Spruce in one instance it must in the other 
also. Abies Canadensis Miller as to name and technical description, 
but not as to plant, is a pure synonym of Pinus Canadensis Linn., thus 
leaving Miller's plant nameless; yet Mr. Tidestrom accepts Picea 
Canadensis (Mill.) Britt. If Pinus Canadensis Linn. (Abies Canadensis 
Mill. as to name bringing synonym) is legitimately construed as the 
Hemlock Spruce, then the nameless plant of Miller, the White Spruce, 
must be given a different appellation than the one by which it is 
now known since two species can not be given the same specific name 
when based upon the same earlier binomial. One or the other must 
drop the specific name Canadensis: if it is to be the Hemlock, then its 
name should be the one heading this article; if the White Spruce, the 
name for it should be Picea @tauca (Moench.) Beissn. (Pinus glauca 
Moench, Verz. 73, 1785.) 
For my part and with all due respect to Mr. Tidestrom, I fail to see 
that he has thrown any new light upon the subject; he has not shown 
the determining incident occurring after 1753 that induced Linnaeus 
to create a new binomial or species, if it were not, as previously main- 
tained by me, the publication of Miller's plate and description. If 
Linnaeus did not know the White Spruce, the plate of Miller illus- 
trating it was second only to an actual specimen in hand and therefore 
he became through studying the figures as familiar with the Spruce as 
he could have been with the Hemlock from an examination of the 
Clayton fragmentary twig, some twenty odd years previously; he was 
at the time (when Miller's figures were brought to his attention) prob- 
ably engrossed with the production of the 2nd Ed. of the Species Plan- 
tarum; his study of the Hemlock was brought to mind; he saw a 
greater resemblance in it to the Spruce than to the Balsam Fir; it 
was, therefore, taken out of Pinus Balsamea and placed under his 
new species, P. Canadensis, where it “should not be considered as ne- 
cessarily belonging to the species, but that it was possible that such 
was the case;" having brought these two species together, that he used 
the old description of his own rather than that of a rival author was per- 
fectly natural, and quite understandable. Since, however, the plate of 
Miller is the determining factor in the creation of Pinus Canadensis, 
it should be considered as the type. 
DEPARTMENT OF Borany, Parke, Davis & Co., 
Detroit, Michigan. 
