EXPLANATION OF THE PLATES. 
PLATE OF GENERA. — Fig. 1, Polypodium (vulgare) ; 2, Grammitis ; 
3, Aspidium (filix-mas) ; 4, Cistopteris (fragilis) ; 5, Woodsia (ilvensis) ; 
6, Asplenium (trichomanes) ; 7, Scolopendrium ; 8, Bleclmum ; 9, Pteris ; 
10, Cryptogramma ; 11, Adiantum ; 12, Trichomanes ; 13, Hymenophyllum 
(tunbridgen.se); 14, Osmunda; 15, Botrychium ; 16, Ophioglossum ; 17, 
Pilularia; 18, Isoetcs ; 19, Lycopodium (selaginoides) ; 20, Equisetum 
(fluviatile). — Note. This Plate shews in many instances the general structure 
of the Ferns, as in Polypodium are seen the spiral vessels of the stem and 
the sheaths of the root ; in Grammitis, Osmunda, Ophioglossum, and Lyco- 
podium, the stomata upon the cuticle ; in Aspidium a scale is seen magnified ; 
and in most of them a view of the tlieca, indu'sium, spores, elastic ring, and 
a cross section of the rachis, as alluded to in the introductory chapters. 
PLATE I. — Fig. 1, Grammitis ceteraeh; 2, Polypodium vulgare; 3 a, P. 
vulg., var. proliferum ; [Z, P. vulg., var. cqmbricum ; 4, P. phegqpteris ; 
5, P. dryopteris; 6, P. calcareuin; 7, Woodsia ilvensis ; 8, W. hyperborea ; 
9, Cistopteris dentata; 10, C. dent., var. anyustata ; 11, C. fragilis; 12, 
C. alpina. 
PLATE II. — Fig. 1, Aspidium lonchitis ; 2, A. lobatum; 3, A. aculoatum; 4, 
A. acul., var. lonchitidoid.es ; 5 a, acul., var. nnyulare ; ft, acul., var. linearis; 
. G, A. thelypteris ; 7, A. oreopteris ; 8, A. filix-mas ; 9. A. cristatum ; 10, 
A. rigidum ; 11, A. spinulosum ; 12, A. dilatatum. 
PLATE III. — Fig. 1, Asplenium septcntrionale ; 2, A. alternifolium ; 3, A. 
marinum; 4, A. trichomanes; 5, A. viride ; 6, A. ruta-muraria ; 7, A. fon- 
tanurn; 8, A. adiantum nigrum; 9, A. lanceolatum ; 10, A. filix-foemina ; 
11, Scolopendrium vulgare ; 12, Pteris aquilina. 
PLATE IV. — Fig. 1, Cryptogramma crispa ; 2, Bleclmum boreale ; 3, Adian- 
tum capillus-vcneris ; 4, Hymenophyllum tunbridgense ; 5, H. wilsoni; G, 
Trichomanes brevisetum ; 7, Osmunda regalis (young plants below) ; 8, 
Botrychium lunaria ; 9, Ophioglossum vulgatum ; 10, Pilularia globulifera ; 
11, Isoetcs lacustris. 
PI. ATE V. — Fig. 1, Lycopodium clavatum; 2, L. annotinum ; 3, L. inun- 
datum ; 4, L. selaginoides ; 5, L. alpinum ; 6, L. selago ; 7, Equisetum 
fluviatile; 8, E. Urummondii ; 9, E. arvense; 10, E. sylvaticum; 11, E. 
limosum; 12, E. palustre; 13, E. hyemale; 14, E. variegatum. 
PLATE VI. (varieties.) — Fig. 1, var. of Polypodium vulgare ; a, the common 
plant; (i, ser Tatum ; y, proliferum ; <1, cambricum ; s , acutum. — Fig. 2, var. 
of Scolopendrium vulgare; a, ft, multifidum ; y, part of a frond dilated at 
the base; £, crispum. — Fig. 3, var. of Cistopteris dentata ; a, pinnule of a 
barren frond; the usual wild state; y, part of a cultivated frond; 
angustata. — Fig. 4, full-size frond of Cistopteris alpina, gathered at Layton, 
1835 (see note page 24) ; a, a barren pinnule (cultivated) ; /3, pinnule from 
a Swiss specimen ; y, pinnule of a curious var. of one of the Cistopterides, 
perhaps of dentata ; (1 believe that this belonged to the late Mr. J. Dickson ; 
I have the frond, which is marked Pol. trifidum, With, (true.) Can this be 
the Welch plant referred to by the latter author?) — Fig. 5, var. of Cistopteris 
fragilis ; n, barren frond ; /3, the usual state ; y, the effect of drought ; 8, 
from a cultivated specimen. — Fig. 6, different states of Aspid. aeuleat.um. — 
Fig. 7, a, variety of Aspid. lobatum ; Botrychium lunaria, with the lower 
