182 Rhodora [SEPTEMBER 
chusetts, the latter is a northern species ranging from Labrador to 
Manitoba, and southward to southern New England, the mountains of 
Pennsylvania, the region of the Great Lakes, northern Missouri and 
the Black Hills. The two species meet chiefly in southern New 
England. 
In both of these species the rootstock is horizontal or nearly so, 
and the young growth appears at the end, in advance of the bases of 
the older fronds, instead of surrounded by them as in A. Filix-femina. 
At the same time the two species differ considerably from one another 
in their underground parts. A. asplenioides has the rootstock dis- 
tinctly creeping, and only partially and incompletely covered by the 
short persistent bases of the fronds, the whole structure being only 
1-1.5 cm. in diameter. The fronds of each season’s growth are loosely 
clustered, and the next season’s growth projects conspicuously beyond 
the bases of the fronds of the current season. A. angustum has a 
much more condensed rootstock completely covered by the long 
overlapping fleshy persistent bases of the fronds, the whole structure 
being 2-5 cm. in diameter. The fronds are usually produced in con- 
siderable numbers, and as the rootstock grows but slowly, they are 
bunched together, but not truly tufted or forming a crown as in A. 
Filix-femina. The new growth stands in front of the fronds of the cur- 
rent season, but does not project conspicuously as in A. asplenioides.! 
The young growth of A. asplenioides is covered with scales which 
are smaller and proportionally narrower than those of A. Filix-femina 
but similar in color and structure. In the American fern, however, 
these scales are for the most part quickly deciduous after growth starts, 
and the stipes and bases of the mature fronds show very few scales, 
and these commonly of very small size (3-5 mm. long, by less than 
1 mm. wide). 
1 I have laid particular emphasis on this point because D. C. Eaton, Ferns of the Southwest, 
U. S. Geog. Surveys West of the 100th Meridian, vi. 330 (1878), says, ‘‘ Moore separates the 
greater part of the North American ferns specifically under the name of Athyrium asplenioides, 
Desv., making two varieties, one with broader and one with narrower pinnules, but the dis- 
tinctive character which he relies mainly upon, the ‘creeping caudex,’ seems to be invalid, as 
our American plants grow in crowns no less decidedly than those of Europe.” The context 
shows that Eaton was not confining these remarks to the western ferns, which are truly tufted, 
but that he entirely ignored the difference between the close crowding of leaves due to a very 
slow horizontal growth of the rootstock, and the true crown which arises when the growth is 
vertical or nearly so. Certainly the quotations in the footnote on p. 179 are very far from 
describing the condition of the rootstock in either of our east American species. It is note- 
worthy that all European botanists who have been dealing with living American plants in culti- 
vation have noted the difference in the underground parts between these plants and A. Filiz- 
femina. 
