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THE 
AMERICAN NATURALIST. 
Vor. x11. — NOVEMBER, 1878. — No. 11. 
ASPIDIUM SPINULOSUM (SWARTZ) AND ITS VARIE- 
TIES 
BY GEO. E. DAVENPORT. 
Po several seasons past I have been making some spe- 
cial examinations of the different forms of Aspidium spinulo- 
sum as found gřowing in Middlesex county, Mass., and offer the 
result not as béing decisive in character, but for the purpose of 
calling attention to the points involved, and inviting further inves- 
tigations in the same direction. 
An opinion prevails with many botanists that ithe large series 
of forms in this protean species so run into each other, and are 
oftentimes so confusing and difficult to place, that it would be 
better to ignore all of the so-called varieties and only recognize 
all forms under the one specific name. How far this opinion may 
Or may not be correct, and founded on scientific principles, pos- 
sibly this note may help to determine. 
I certainly am not in favor of recognizing as a variety any form 
not possessing some well marked and permanent character to 
distinguish it from the recognized typical form of any species. I 
have so often expressed myself on this point that I do not 
feel under any apprehension of appearing inconsistent in endeav- 
Oring to show that the so-called var. intermedium is a good 
variety at least, if indeed it be not a good species. 
The precise distinctions between Aspidium spinulosum Swz., 
and its var. intermedium have not as yet been clearly enough 
pointed out, so that the greatest confusion has prevailed in the 
effort to verify the presence here of true spinwlosum, and to dis- 
cover the differences between it and the variety; the usual 
_ “assumption having been that nearly if not all of our American 
plants belonged to the latter form. 
VOL. XIT.—NO XI, 48 
