138 Rhodora [Jury 
August 18, 1894, Suksdorf, no. 2336; crevices of rock, Mt. Baldy, 
July 7, 1902, Conard, no. 288. 
When he published var. columbianum, Gilbert at least knew of P. 
hesperium for he included it in his List, but all the points emphasized 
by him: "the short stipes and narrow fronds, the very glandular 
surfaces, the odd pinna at base of frond, the deep lobations of lower 
pinnae, and the occasionally green-gold hue of lower surface," are 
found in one specimen or another of P. hesperium. The measurement 
of the fronds nearly coincide with those originally given for P. hes- 
perium. (“6 to 13 em. long, 2 to 344 em. broad."—Gilbert; 3 to 8 
inches [7.3 to 19.6 em.] long, 1 to 124 inches [2.4 to 7.2 em.] broad— 
Maxon); the glandularity of the frond is extremely variable, though 
Maxon originally indicated some glandularity for P. hesperium; and 
the alternate pinnae (and consequently “odd pinna at base of frond”) 
were specially emphasized by Maxon and they were described with 
“margins obscurely (or less often, decidedly) crenate.”’ 
When he published P. hespervum as a species, Maxon said, “It is 
barely possible, but hardly probable, that the species here described 
is identical with the var. rotundatum of Milde." Surely the larger 
development of the plants (such as G. R. Vasey’s no. 41 or Whited’s 
no. 1392 from Lake Chelan, the type region of P. hesperium) are 
difficult to distinguish from var. (or forma) rotundatum and Mr. J. K. 
Henry (Fl. So. Brit. Columb. 2) reduces them outright; but the 
pinnae are too broad and short to satisfy Luerssen's requirement 
(Farnpfl. 56) of pinnae “linealisch oder lünglisch-linealisch;" and 
although the larger plants closely approach Alaskan and Norwegian 
specimens of forma rotundatum, var. columbianum may stand as : 
fairly differentiated extreme of the western mountains. In its nar- 
rower forms passing insensibly to 
Var. PERPUSILLUM Clute, Fern Bull. xviii. 98 (1910).—Fronds 
coriaceous, linear-oblong, 0.3-1.7 dm. long, 1-2 cm. broad; their 
6-22 pairs of remote alternate pinnae 2-5 mm. wide.—Mountains 
of Colorado, New Mexico and Arizona. CoLorapo: Brandegee. 
New Mexico: lower side of cliff, vicinity of Brazos Canyon, Rio 
Arriba Co., August 20, 1914, Standley & Bollman, no. 10,626. 
Var. PYGMAEUM Schur, Enum. Pl. Transsilv. 830 (1866).—Stipe 
1-7 em. long, slender: frond ovate-lanceolate, ovate or deltoid, 2-8 
em. long, 2-3 em. broad, with only 1-7 pairs of broad-oblong to 
narrowly ovate round-tipped pinnae or segments.—Forma pumilum 
Hzusm. ex Luerss. Farnpfl. 58 (1889).—' The following American 
