RHIZOMA FILICIS. 735 



the regular flattened shape, usual in many suberous coats. Within 

 this cortical layer, there is a circle of about 10 large vascular bundles, 

 besides a large number of smaller ones scattered beyond the circle. 

 The leaf-bases exhibit a somewhat different structure, their vascular 

 bundles, usually 8, forming but one diffuse circle. 



The cells of the parenchyme contain starch, greenish or brownish 

 granules of tannic matter, and drops of oil. In the green, vigorously 

 vegetating parts of the rootstock there are numerous smaller and 

 larger intercellular spaces, into which a few stalked glands project, as 

 shown by Prof. Schacht of Bonn in 1863. These globular glands 

 originate from the cells bordering the intercellular spaces. After their 

 complete development, and the appearance of starch in the adjacent 

 parenchyme, they exude a greenish fluid, which when thin slices of the 

 rhizome are kept some time in glycerin, solidifies in acicular crystals.' 

 Such glands appear to be wanting in most of the aUied ferns, such as 

 Aspidium Oreopteris Sw. and Asj-ylenium Filix foemina Beruh. They 

 h^ve been observed by one of us (F.), in the small rhizome of A. spinu- 

 ffowTO Sw. Similar glands, but not exuding a green liquid, occur 

 between the palese below the vegetating cone of the rootstock. 



Chemical Composition— Of the numerous examinations which 

 We been made of this druo-, those of Bock (1852), of Luck (1860), and 

 of Kruse (1876), may be especially mentioned. Besides the universally 

 distributed constituents of plants, there have been found in the rhizome 

 5 to G per cent, of a green fatty oil, traces of volatile oil, resin tannin 

 (Luck's Tannaspidic and Pteritannic Adds) and crystalhzable sugar, 

 which according to Bock is probably cane sugar. 

 ^ The medicinal ethereal extract, of which the rhizome yields abou 

 8 per cent., deposits a colourless, granular, crystalline substance, not mi 

 ty Peschier as early as 1826, and subsequently designated by Luck, 

 ^hcic Acid. Grabowski (1867) assigned it the fomu a C H U^ 

 We learn from Prof Bucbheim that he regards filicic acid as the souice 

 ?f the medicinal efficacy of the drug. By fusion with potash ^hc^ acid 

 f. converted into phloroglucin and butyric acid The f ^ Jj^ffCi 

 twn of the extract consfsts mainly of a glycende called to Mrom 

 which Luck obtained by saponification two acids, the one volatile, f Uos 

 ^^ylic Acid, the other non-volatile, termed Filixohc Ac,d. 

 . Malin (18G7) showed that the tannic acid of ni.Jefern^ay^^^ 

 decomposed by boilinc. dilute acids into sugar and a red substance. 



5;\oil of disagreLble od^ou'r. The "a-^. ,^t ,ttSn -y acid body. 

 «'d not evolve a similar odour, nor did t _ contain any ^^^^^ 



f «mall quantity of essential oil was obtained by mea ^^^^_ 



f;:onj the alcoholic extract of the fresh but not o the a ^^^_ 



^tock. The rhizome of male fern yields 2 to 3 per cent. 



J The .Jen^ieal nature of this body re- ^ ^"^ j^o'lf ^'t/^'^^^^"^ 



chl. Y ^*"<^ ^"'l, accompanied by 

 •^hlorophyl and essential oil. 



