174 Rhodora [OCTOBER 
able activity in the study of American ferns since 1908 that the changes 
discussed below are called for. 
Aspidium.— It is a very great pity that in his work on the indis- 
pensable Index Filicum and on what promises to be his classical mono- 
graph of the shield ferns, Christensen should have overlooked the ear- 
liest valid name for this genus. The name which he took up, Dryop- 
teris Adans., has long been the subject of controversy. As has several 
times been pointed out,! its publication was inadequate under the 
International Rules: for that reason, it was rejected by the editors of 
the Manual and the next earliest name known to them, Aspidium Sw., 
taken'up. In 1910, however, Nieuwland discovered that there exists 
an entirely valid name, Thelypteris of Schmidel, applied to the marsh 
fern, Acrostichum Thelypteris L., and published in 1762, a year earlier 
than Dryopteris, with three or four pages of description and comment 
and two very excellent plates.? 
There can be little question that this is the correct name for the 
shield ferns. Farwell has, indeed, put forward a rival in Filix Hill 
(1755).* Hill, however, merely uses the doubtful binomials Filix Mas 
and Feliz Foemina as the headings of paragraphs in his Family Herbal 
containing popular descriptions in English of the male, fern and the 
bracken respectively. Such use can hardly constitute publication 
under any nomenclatorial code, certainly not under the International 
Rules. Thelypteris remains the earliest valid name for Aspidiwm of 
the Manual: and, much as one regrets adding another to the numerous 
names this genus has already borne, it must be taken up. Rules are 
of no use unless conscientiously followed. 
Fernald ? has pointed out that Aspidium spinulosum, var. dilatatum, 
f. anadenium differs from typical var. dilatatum of Europe not only in 
the absence of indusial glands but also in the characters of its scales, 
and that it should be regarded as a coórdinate geographic variety. 
As such it was given a name, var. americanum by Fischer in 1848. 
Asplenium.— the lady ferns and their allies.— Recent study has 
pretty conclusively shown that Athyrium is a good genus, differing 
constantly from Asplenium in the character of its scales, the anatomy 
of its stipe and its general habit and appearance. It constitutes a 
1 For instance, in Ruopora xxi. 10 (foot-note) (1919). 
? Am. Midland Nat. i. 226 (1910). 
3 Ann. Rep. Mich. Acad. Sci. xviii. 79 (1917). 
4 Hill, Family Herbal 141 (1755). 
5 Ruopona, xvii. 44 ff. (1915). 
