5 
p. 656) originally described, and which some still regard as a distinct 
species. 
In drawing up his characters,- Pursh seems to have relied chiefly 
on the presence or absence of pubescence as the distinguishing fea- 
tures between his plant and B, Virginianiun. But an examination 
of any considerable number of specimens will show that pubescence 
is sometimes present in gracile and wanting in Virginianum^ so that 
this character was not well founded. The other characteristics are 
only such as might be expected in plants in different states of de- 
velopment. 
The plant first appears as a variety of B, Virginianum in Hook- 
er's Botanical Miscellany (Vol. iii., p. 223, 1833), where it was pub- 
lished as such by Hooker and Greville from specimens communi- 
cated by Dr. Torrey, who {vide same authorities, /. r.) regarded it 
merely as a variety. Later (1843), Dr. Torrey so published it in his 
Flora of New York, and, according to Milde (Botrychiorum Mon- 
ographia), in 1847 Presl also published it as a variety in the Sup- 
plement to his PteridographiEe. This disposition of the plant was 
afterwards confirmed by Dr. Milde (/. r.), and is now very generally 
accepted. 
The probabilities are, however, that this form is rather the young 
state of B, Virginiamwi than a true variety, Clarence Lown writes 
me that with him it is not uncommon, but that it is impossible to 
tell where the so-called variety ends and Virginianum begins ; and 
such is the testimony of the specimens which have passed through 
my hands. It is more than probable that if we should trace the 
development of B. Virginianu?n from the prothallus upward, year 
after year, we would find the young plant at first smooth, and with 
an ever increasing pubescence with age. We could thus account 
for the infrequency of pubescence in young plants, some retaining 
their smoothness longer than others. 
• Mr. Suksdorf's specimen is typical of Pursh 's plant. It is every- 
where smooth, and the bud itself is wholly free from any trace of 
pubescence. 
In the vernation of mature specimens of B. Virginianu?n the 
bud is invariably clothed with a hairy covering ; but, in these younger 
plants, the bud is but scantily clothed at the most, or is wholly 
smooth (as in Mr. Suksdorf's specimen) — a circumstance which does 
not appear to have been noticed by any one heretofore (not even by 
Milde, who more than once distinctly notices the hairiness of the 
bud in^. Virginianum), and which was overlooked by myself in my 
Note? on the Vernation in Botrychia in the Torrey Bjlletin for 
JanuaryjiSyS (Vol. vi.,p. 193). Probably a truer diagnosis of the ver- 
nation in this species than heretofore published will be: bud smooth 
at first (in the youngest state), finally pubescent, the hairy cover- 
ing of the mature bud having only gradually been taken on with age. 
This, possibly, may also be true of the vernation in B* ternatuntj 
where the bud is even more densely clothed with hairiness ; but I 
have not as yet seen, even in my smallest specimens, a bud of that 
species wholly free from pubescence. Its vernation, therefore, may 
remain as previously described (A c). 
