1924| Fernald,—Polystichum mohrioides 91 
so, saying clearly of the Lemmon plant: “At first I believed it to be a 
distinct species.”! Similarly the great Swiss specialist upon the ferns, 
Christ, in monographing Polystichum Š Mohrioides had no hesitation 
in treating P. Lemmoni as identical with P. mohrioides (which, as 
understood by him, was chiefly var. elegans). 
In his discussion of the ferns of temperate South America collected 
by Skottsberg, Christensen? points out the important characters 
which separate P. mohrioides from P. aculeatum and its allies; namely, 
the fleshy texture, scaleless surfaces of the fronds, thick and flat ribs 
and the large and immersed stomata (so immersed that under a good 
lens the lower surfaces of the fronds appear pitted or punctate). 
The fleshy texture, flat ribs and punctate lower surfaces are all obvious 
enough in P. scopulinum, and the fronds are either with or without 
some scales on the lower surface, but this latter character 1s inconstant, 
some sheets of perfectly good P. mohrioides, var. typicum Christensen 
from the Falkland Islands (coll. Cunningham, January 21, 1868) 
before me showing numerous slender scales among the sori. The 
Cunningham specimens are quite like the original plate of Aspidium 
mohrioides and in outline, size, texture and punctation they are so 
close to several North American specimens of P. scopulinum that 
only the keenest inspection reveals slight differences. Thus Parish’s 
material from Snow Canyon, San Bernardino Co., California, is a very 
close match in all these characters for the Cunningham plant and 
for the original plate. All the Falkland material I have seen, however, 
has the basal scales of the stipe darker and firmer than in P. scopuli- 
num, although the Fuegian specimens (var. plicatum) have them as 
pale and thin. 
P. scopulinum is regularly defined as differing from P. mohrioides 
and P. Lemmoni in the sharper and more acicular tips of the upper 
lobes or teeth of the pinnae. In general this character holds, but in 
the Cunningham material from the type-region of P. mohrioides the 
teeth of the lower pinnae are quite as sharp as in some of the North 
American plants, while in the Parish material above cited only the 
lowest pinnae show the sharp teeth, the upper having them quite 
as blunt as in the most ideal P. mohrioides or in P. Lemmont. Further- 
more the plant of Marion Island has some of the pinnae quite as 
spinulose-toothed as in the most extreme P. scopulinum. 
! Eaton, 1. c. 128. 
2 Christ, Ueber die australen Polystichum-Arten. Arkiv för Bot. iv. No. 12: 1-3 
(1905). 
3 Christensen, l. c. 18. 
