29. Nephrodium Filix Mas, Richard.—Male Shield Fern.

Sex. Syst. Cryptogamia, Filices.
(Rhizoma.)

Synonymes.—Polypodium Filix mas, Linn.; Aspidium Filix mas, Swartz.

History.—Fern-root was employed by the ancients in medicine. Theophrastus [Hist. Plant. lib. ix. cap. xx. and xxii.] notices two kinds of fern; the male, which he calls πτέρις, and the female, termed δηλυπτερις. Dioscorides [Liv. iv. cap. clxxxvi and clxxxvii. Sibthorp (Prodr. Fl. Graecae, vol. ii. p. 274) puts a query whether Aspidium aculeatum, Willd. be not the πτέρις of Dioscorides? But in the Pharmacopaea Graeca of 1837, πτέρις is given as the modern Greek name of Aspidium Filix mas.] also mentions these two ferns, and states that the πτέρις is by some persons called βλήκνον, by others πολύρριζον. Pliny [Hist. Nat. lib. xxvii. cap. lv.] notices both ferns, and says the pterin is supposed to be the male fern (filix mas).

Botany. Gen. Char.—Sori roundish, scattered. Indusium orbicularireniform, fixed by the sinus.

Sp. Char.—Fronds bipinnate, pinnules oblong, obtuse serrated, their stalk and midrib chaffy. Sori near the central nerve (Hooker).

The rhizome is large, tufted, and scaly. The leaves grow in a circle to a height of 3 or 4 feet.

Hab.—It is an indigenous plant, frequent in woods and in shady banks. It is a native of other parts of Europe, of Asia, of the North of Africa, and of the United States of America.

Description.—The subterraneous stem (rhizoma; caudex; fern root, radix filicis, officin.) lies obliquely in the ground. It varies in length and breadth, according to its age. For medical purposes it should be from six or more inches long, and from half an inch to an inch or more broad. It is almost completely enveloped by the thickened bases of the footstalks of the fallen leaves. These bases (phyllopodia) are arranged closely around the rhizome in an oblique direction, overlapping each other. They are one or two inches long, from three to five lines thick, curved, angular, brown, surrounded near their origin from the rhizome by two or more shining, reddish yellow, thin, silky scales (ramenta). The radicle fibres (root, properly so called) arise from the rhizome between these footstalks.

The fern root of the shops consists of fragments of the dried thickened bases of the footstalks (phyllopodia), to which small portions of the rhizome are found adhering, and of the root fibres.

Internally, the rhizome and footstalks are, in the recent state, fleshy, of a light yellowish-green colour; but in the dried state, yellowish or reddish-white. Iodine colours the fresh rhizome bluish black, indicating the presence of starch; particles of which may be recognized by the microscope. In a transverse section of the rhizome, we observe five or six, or more, bundles of woody fibres and scalariform ducts. These bundles are arranged in a circle, are of a reddish-white colour in the recent rhizome, but yellow in the dried one.

The dried root has a feeble, earthy, somewhat disagreeable odour. Its taste is at first sweetish, then bitter astringent, and subsequently nauseous, like rancid fat.

Collection.—The rhizome should be collected in the month of July, August, or September. The black portions, fibres, and scales, are to be removed, and the sound parts carefully dried and reduced to powder: this is of a yellowish colour, and is to be preserved in well-stoppered bottles. Both the whole rhizome and powder deteriorate by keeping.

Fern buds (gemmae filicis maris) which are sometimes employed in medicine, are to be collected in the spring.

Composition.—Fern rhizome was analyzed in 1805 by Vauquelin [Ann. Chim. iv. 31.], in 1821 by Gebhard [Diss. inaug. in Pfaff's Syst. d. Mat. Med. 7er Bd. 219.], in 1824 by Morin [Journ. de Pharm. x. 223.], in 1826 by Wackenroder [De Anthelm. regni Vegetab.], and by Geiger [Handb. d. Pharm. 1829.]. Subjoined are the results of the analyses of Geiger and Morin:—

The anthelmintic property of the rhizome resides in the oil (oleum filicis maris). Luck [Ann. der Chem. u. Pharm. Bd. liv. 1845; also Chem. Gazette, vol. iii. p. 369.] obtained from the granular sediment which forms in oil of fern, tabular rhombic plates, whose formula was C₅₉H₃₈O₂₀ (probably it should be C₆₀H₃₆O₂₀), a brown substance soluble in alcohol and alkaline liquids, and whose formula was C₁₀₅H₅₄NO₄₅ and a gray body, insoluble in all solvents, except caustic alkalies, and whose formula was C₂₄H₁₂NO₈.

Batso [Inaug. Diss. 1826, quoted in Goebel and Kunze's Pharm. Waarenk.] found a peculiar acid (acidum filiceum) and an alkali (filkina) in the rhizome.

Fern buds contain, according to Peschier [Quoted by Soubeiran, Nouv. Traité de Pharm. t. ii. p. 159, 2nde Ed.], a volatile oil, brown resin, fat oil, solid fatty matter, green-colouring principle, a reddish-brown principle, and extractive.

Characteristics.—The presence of tannic acid in the aqueous decoction of fern rhizome is shown by the sesquisalts of iron producing a dark green colour (tannate of iron), and by a solution of gelatin causing a yellowish precipitate (tannate of gelatin). No indication of the presence of a vegetable alkali in the decoction can be obtained by tincture of nutgalls. If the rhizome be digested in alcohol, and afterwards boiled in water, the decoction when cold forms, with a solution of iodine, a dingy blue precipitate (iodide of starch).

Physiological Effects.—These are not very obvious; but they are probably similar to those caused by other astringents. Large doses excite nausea and vomiting.

Uses.—It is only employed as an anthelmintic. Theophrastus, Dioscorides, Pliny, and Galen, used it as such. The attention of modern practitioners has been directed to it principally from the circumstance of its being one of the remedies employed by Madame Nouffer, the widow of a Swiss surgeon, who sold her secret method of expelling tape-worm to Louis XVI. for 18,000 francs [Trait. contre le Taenia, &c. 1776, quoted by Bremser, Sur les Vers Intest.]. At the present time fern rhizome is but seldom employed in this country, partly because the efficacy of Madame Nouffer's treatment is referred to the drastics used, and partly because other agents (especially oil of turpentine) have been found more effectual. "It is an excellent remedy," says Bremser [Op. cit. p. 422], "against Bothriocephalus latus [the tape-worm of the Swiss], but not against Taenia Solium, [the tape-worm of this country]; for though it evacuates some pieces of the latter, it does not all of it."

Administration.—It may be administered in the form of powder, of oil or ethereal extract, or of aqueous decoction. The dose of the recently prepared powder is from one to three drachms. Madame Nouffer's specific was two or three drachms of the powder taken in from four to six ounces of water in the morning fasting, and two hours afterwards a purgative bolus, composed of calomel ten grains, scammony ten grains, and gamboge six or seven grains. The bolus was exhibited to expel the worm which the fern rhizome was supposed to have destroyed.

The Etherial Tincture of Male Fern Buds (prepared by digesting 1 part of the buds in 8 parts of ether) has been used with success by Dr. Peschier (brother of the chemist of that name), and by Dr. Fosbroke [Lancet for 1834-35, vol. ii. p. 597.] as a vermifuge.

OLEUM FILICIS MARIS; Oil of Male Fern.—The impure oil of fern (called olium filicis Peschieri, extractum filicis aethereum, seu balsamum filicis), recommended by Peschier [Journ. génér. de Med. 1825, p. 375.], is an ethereal extract, and is composed, according to its proposer, of a fatty matter, resin, volatile oil, colouring matter, extractive, chloride of potassium, and acetic acid. A pound of the rhizome yielded Soubeiran [Nouv. Traité de Pharm. ii. 161, 2nde éd.] an ounce and a half of thick black oil, having the odour of fern. It may also be prepared from the buds as above stated. The dose is from half a drachm to a drachm, in the form of electuary, emulsion, or pills: an hour afterwards, an ounce or an ounce and a half of castor oil should be exhibited. Numerous testimonies of its efficacy have been published [Dierbach, Neuesten Entd. in d. Mat. Med. Band 1, 1837.]. I have tried it in several cases of tape-worm, but without success. By substituting alcohol for ether, twelve or thirteen drachms of oil can be obtained from 2 2/3 lbs. of the rhizome [Journ. de Chim. Méd. t. v. 2nde Ser. p. 68.].

The Elements of Materia Medica and Therapeutics, Vol. II, 3th American ed., was written by Jonathan Pereira in 1854.