382 CllYPfOGAMlA— Fll.lCES. [Polypodium. 



ing a fine powdery substance, others 3-valved, containing a few 

 large grains or seeds. — Named from 'auxo;, a ivoff, and ~ouc, 

 'xobo;, a. foot, which the branches of some species arc supposed 

 to resemble. 



SuBORD. II. MARSILEACE^. Br. 



Capsules without a ring, within involucres that are near the 

 root of the phmt. — Aquatics. 



1. IsOETES. Involucres formed by the swollen base of the 

 leaves, 1-celled. Seeds angular, inserted upon many filiform 

 receptacles. — Named from /(Tog, equal or alike, and sroc, the 3/ear, 

 or ever-green. 



2. PiLi'LARiA. Involucres solitary, nearly sessile, globose, 

 coriaceous, 4-celled : each cell containing 2 diiFerent kinds of 

 bodies {anthers ? and pistils ?). — Name ; pilula, a little pill, 

 which its fructifications resemble. 



SuBORD. III. EQUISETACE.E. Rich. 



Fructifications terminal, in spikes or catkins, consisting of pel- 

 tate, polygonous scales, on the underside of which are from 

 4 — 7 involucres, which open longitudinally and contain nume- 

 rous globose bodies, enfolded by 4 filaments, clubbed at their 

 extremities. — Stems rigid, leaJiess,joi7ited, striated,the articu- 

 lations sheathed at the base. 



I. EQUISETU3I. Character of the Genus the same as that of 

 the Order — Named from Equus, a horse, and seta, a hair, or 

 biistle ; meaning horse-tail. 



CRYPTOGAiMIA—FILICES. 



1. GRAMMfxis. Sw. Grammitis, 



1. G. Ceterach, Sw. {scaly Grammitis^; fronds pinnatifid 

 covered beneath with imbricated chafi^y scales, segments ovate 

 obtuse, scales entire. — Scolopendrium, E. Bat. t. 1244. — Asple- 

 nium, L, 



Rocks and walls, most abundant in limestone countries, and the south 

 of England and Ireland: rare in Scotland. Near Perth and Paislej'. 

 Kilfinnan, Argyleshire, Mr S. Murray. — Mr W. Wilsou finds evident 

 traces of an involucre on the lower side of the sorus, viz. "a narrow 

 membrane fringed with the same chaffy scales, which cover the back of 

 the frond." 



2. Polypodium. Linn. Polypody. 



1. P. vulgdre, L. {common Polypody) ; fronds deeply pinnati- 

 fid, the segments linear-lanceolate obtuse crenulate approximate, 

 upper ones gradually smaller. E. Bot. t. 1 149. 



Rocks, walls, trunks of trees and banks, frequent. — The lobes are 



