Part 2

Onoclea Germanica, Hooker, Sp. Fil., iv., p. 161.—Hooker & Baker, Syn. Fil., p. 46.

Osmunda Struthiopteris, Linnæus, Sp. Pl., p. 1522.

Struthiopteris Germanica, Willdenow, “Enum, p. 1071;” Sp. Pl., v., p. 288.—Link, Fil. Hort. Berol., p. 38.—Hooker, Fl. Bor.-Am., ii., p. 262.—Torrey, Fl. New York, ii., p. 486.—Gray, Manual, ed. i., p. 623, etc.—Koch, Syn. Fl. Germ. et Helv., ed. iii., p. 739.—Williamson, Fern-Etchings, t. 44.

Struthiopteris Pennsylvanica, Willdenow, Sp. Pl., v., p. 289.—Pursh, Fl. Am. Sept., ii., p. 266.—Torrey, Compendium, p. 385.—Bigelow, Fl. Boston., ed. iii., p. 421.

Struthiopteris, the genus only, Willdenow, in Berl. Mag., 1809, p. 160.

Hab.—Low grounds, especially in fine alluvial soil subject to the overflow of rivers; from the Saskatchewan and Lake Winnipeg to New Brunswick, and southward to Pennsylvania and Illinois. Mentioned by Alexander Braun as coming from Arkansas. From Lapland to Sicily, and eastward to the Amoor region, Sachalin and Kamtschatka. Not known in the western parts of either Europe or America.

Description:—The ostrich-fern is one of our finest ferns, being surpassed in grandeur only by Acrostichum aureum, Woodwardia radicans, and perhaps Osmunda regalis. The plant is propagated chiefly by long and slender stolons, bearing appressed rudimentary stalk-bases. These stolons are said by Sachs to originate from buds formed on the stalks near the base: they run underground for several inches or a foot, and at the end rise to the surface and there thicken into a short erect caudex, covered by imbricating stalk-bases, and throwing up from the apex a grand vase-like circle of foliage, which is often higher than a man’s head, and sometimes extends above his utmost reach.

The stalks are seldom over a foot long: they are flattened, blackish, and chaffy at the base, but above ground they are green, drying dull-brown, somewhat four-sided, and deeply channelled in front, when dried furrowed on the sides also. They contain two flattened fibro-vascular bundles. The stalks of the sterile fronds are rather longer than the others, but more rigid, and remain erect till the second year.

The sterile fronds are oblong-lanceolate in outline, gradually narrowed to the base from near the middle and abruptly short acuminate. The pinnæ are usually of nearly equal breadth from the base to beyond the middle. They are pinnatifid to within a line of the midrib into numerous oblong and obtuse segments, the veins of which are free, simple and pinnately arranged on a midvein.

The fertile fronds are produced late in the summer, and are contracted, much shorter than the others, and very rigid. The pinnæ are sometimes nearly entire, and in other examples pinnately lobed. The margins are very much recurved, so that the pinnæ are pod-like, and either sub-cylindrical or somewhat moniliform. The venation is free, and the sori are dorsal on the veins. Mr. Faxon writes: “The indusium can be detected only when the fertile frond is very young, and appears as a very delicate, lacerate membrane, attached at the base of the receptacle, and serving to separate the sorus from its neighbors. I have not found it in any case hood-like as in O. sensibilis. The sori are quickly confluent, and all trace of the indusium is soon lost. The membranaceous edge of the transformed fertile pinna is attached near the bases of the inferior sori and a fold is usually found pressed against the sori as seen in the drawing (Fig. 3). This is usually ruptured, so as to leave a portion attached at the base of the sorus, and must not be mistaken for the true indusium, which is within.”

The sporangia have twenty-six or twenty-eight articulations of the ring. The spores are dark-colored and ovoid.

Imperfectly fertile fronds are often found, which are analogous to the “obtusilobata” condition of O. sensibilis.

ALPINE BEECH-FERN. FRAGRANT WOOD-FERN.

PHEGOPTERIS ALPESTRIS, Mettenius. Alpine Beech-Fern.

Phegopteris alpestris:—Root-stock short and thick, erect or oblique; stalks sub-terminal, four to ten inches long, bearing a few brown spreading scales near the base; fronds one to two feet long, oblong-lanceolate, membranaceous, smooth, pinnate with delicately bi-pinnatifid deltoid-lanceolate pinnæ, the lower ones distant, and decreasing moderately; pinnules ovate-oblong or oblong-lanceolate, doubly incised and toothed; sori small, rounded, naked, usually copious on all or all but the lowest pinnæ.

Phegopteris alpestris, Mettenius, Fil. Hort. Lips., p. 83; Phegopteris, p. 10.

Polypodium alpestre, Hoppe, “in Spreng. Syst. Veg., iv., par. ii., p. 320.”—Koch, Syn. Fl. Germ., “ed. 2, p. 974;” ed. 3, p. 731.—Moore, Nat. Pr. Brit. Ferns, t. vii.—Hooker & Arnott, Brit. Fl., ed. 7, p. 582.—Hooker, Brit. Ferns, t. vi.; Sp. Fil., iv., p. 251.—Hooker & Baker, Syn. Fil., p. 311.

Aspidium alpestre, Swartz, Syn. Fil., p. 421.—Schkuhr, Krypt. Gew., p. 58, t. 60.

Asplenium alpestre, Mettenius, Asplenium, p. 198, t. vi., figs. 1-6.

Pseudathyrium alpestre, Newman, “Phytologist, iv., p. 370;” Hist. Brit. Ferns, ed. iii., p. 200.

Athyrium alpestre, “Nylander;” Milde, Fil. Eu. & Atl., p. 53.

Polypodium rhæticum, Linnæus, Sp. Pl., p. 1552, fide Schkuhr, l. c.; but Moore thinks the plant not the same.

Aspidium rhæticum, Swartz, Syn. Fil., p. 59.—Willdenow, Sp. Pl., v., p. 280.

Hab.—Among rocks at high elevations; on Lassen’s Peak, Mount Shasta, Pyramid Peak, Mount Rose, and other high points in the Sierra of California, Brewer, Lemmon, Muir; Cascade Mountains of British Columbia, Lyall. In the Alps and the mountains of Northern Europe; also in the Caucasus, and in Asia Minor.

Description.—The root-stock is rather short, but branching, and seems to form great entangled masses. The fronds stand in a crown or circle, rising from the end of the root-stock, which is made thick and heavy with the chaffy bases of former stalks. Mr. Lemmon writes thus: “It grows in a limited locality, so far as I know, near the summit of Mount Rose, near Webber Lake, and say at an elevation of 7,000 feet; lat. 39½° N. Fronds collected into a large mass four feet across, short at the circumference, in the centre three feet high; most of them fertile, and densely so, as in the specimen sent.”

The stalks are usually but a few (four to six) inches long, and in the dried specimens of a brownish straw-color, becoming nearly black at the base. They bear a few large ferruginous chaffy scales, and are deeply channelled and furrowed. The fibro-vascular system of the stalk is altered by contraction in drying, but apparently agrees with Dr. Milde’s description of Athyrium: “There are two oblong peripheric bundles in the base of the stalk, which, at the base of the lamina, are united into one of a horse-shoe shape by an arc parallel to the back of the stalk.” In the middle of a stalk from one of the California specimens I find two systems of ducts, one on each side of the stalk, and the two united by a curved and contorted border of firm blackish tissue (sclerenchyma).

The fronds are from one to two feet long, and from three to six inches wide. In general shape they are oblong-lanceolate, acuminate, and slightly narrowed at the base. The texture is softly membranaceous, and both surfaces are smooth. The primary pinnæ are numerous, the lower ones gradually farther apart: their shape is lanceolate from a broad base. They are usually twice pinnatifid, the pinnules being connected by a very narrow foliaceous border along the midribs. The ultimate segments are sharply toothed. The fruit-dots are very abundant, and usually are found on all the pinnæ. They are placed on the back of the free veinlets, and are apparently devoid of indusium; though Dr. Mettenius has discovered on young fronds an exceedingly delicate and fugitive indusium, resembling in some degree that of Asplenium § Athyrium. Accordingly, in his later work, he referred the species to the genus Asplenium, placing it next to A. Filix-fœmina. Milde, in his work on the ferns of Europe and Atlantis, sought to re-establish Athyrium as a genus, and placed this fern in it, saying “sori ... rotundi, primum breviter oblongi indusio fugaci minutissimo ciliato instructi.” The spores are ovoid, and apparently covered with anastomosing raised lines. Those I have examined are fuscous-brown, but Milde says “sub-nigræ verrucosæ.”

There is a European var. flexilis, with very narrow, nearly sessile fronds, and the pinnæ often deflexed, which has not been observed in America.