15 67 
closely resembles the var. affine (Fisch. and Mey.), occurs in the Rocky Mts. (Mon- 
tana, Idaho), where rather typical forms also are met with (Utah, New Mexico, 
Arizona, California). 
In Mexico, where the following species is frequent, true D. filix mas is rare; 
the specimens referred here belong to a form, which approaches the following 
species, but it does not differ from JD. filix mas in the main characters. This 
Mexican form varies considerably in the degree of cutting, from merely bipinna- 
tifid to deeply tripinnatifid. Very large specimens collected by ScuarrNEnR (B, 
without exact locality) are not unlike the subspecies elongata (Sw.) and belong 
perhaps to a distinct variety. 
State of Mexico: Nevada de Toluca, J. N. Rose and PaiNTER nr. 7944 (W). 
State of Oaxaca: Sierra de San Felipe, CHanrEs L. SurrH nr. 2076 (W). 
State of Puebla: Ixtaccihuatl, 2610 m., F. Nicoras nr. 5550 (RB). 
3. Dryopteris paleacea (Sw.) C. Chr. Amer. Fern Journal 1: 94, 1911. 
Syn.: Aspidium paleaceum Sw. Syn. 52, 1806; Fourn. Mex. pl. 1: 92, 1872. 
Aspidium parallelogrammum Kze. Linnaea 15: 146, 1839. 
Dichasium parallelogrammum Fée, Gen. 302 tab. 23 B fig. 1. 1850—52. 
Aspidium resp. Nephrodium filix mas var. parallelogrammum resp. palea- 
ceum auclt. plur. 
Aspidium crinitum Mart. et Gal. Mém. Ac. Brux. 15: 66 tab. 17, fig. 2, 1842. 
Aspidium Pseudo-Filix-mas Fée, 8 mém. 103, 1857. 
Aspidium chrysocarpon Feé, 8 mém. 108, 1857. 
Type from Peru (LaGasca). Not seen. 
It is beyond question that A. paleaceum Sw. is identical with A. parallelo- 
grammum Kze. from Mexico, leg. KArwinsky (B!). The specific name has been 
attributed to DoN, who under that name described a similar form from Himalaya 
(Prod. Fl. Nepal. 4, 1825), which is A. patentissimum Wall. 
In treating this widely distributed American fern as a species, which by most 
authors is referred to JD. filiv mas as a variety, I have several reasons for doing 
so. It is very often identified with Central-Asiatic forms of D. filix mas, espe- 
cially with the varieties patentissima and fibrillosa Clarke; I have, however, never 
seen Asiatic forms, which entirely agree with the American one. J. paleacea is a 
rather uniform species, which constantly differs from D. filix mas by the following 
characters: 1) Stipe and rachis very densely clothed with 1—2 cm. long, narrow, 
blackish or reddish, glossy, divaricating scales, 2) lamina always bipinnatifid, never 
bipinnate, 3) pinnz not widened at base, long acuminated and sharply serrated to 
the very apex, the lower ones, which are somewhat reduced, not subdeltoid, 4) 
segments with parallel, entire or very faintly toothed edges, the apex truncate with 
3—5 short teeth, the basal ones not enlarged and lobed (still often with an interne 
auricle), rarely free, 5) texture chartaceous or coriaceous. — The indusium is large 
and often biscutelloid (as FÉE termed it), which is especially the case in the an- 

