159 
The volume contains 360 pages of letter-press and 136 illustrations 
engraved on wood; many of the figures are new, but of these, the fol- 
lowing only require to be noticed : — two forms of Capillus Veneris ; 
a copious and elaborate illustration of Gymnogramma leptophylla, 
- exhibiting a variety of forms; the vernation of Kupteris, contrasting it 
with Pteris; Gymnocarpium Robertianum; Cystopteris Dickieana; 
Pseudathyrium alpestre ; Pseudathyrium flexile ; Asplenium acutum ; 
Phyllitis Scolopendrium, showing the cordate bases of the fronds, 
not visible in the former illustration; Botrychinm rutaceum; and 
Ophioglossum lusitanicum: with the exception of Scolopendrium, 
which is reduced, all these are exactly of the natural size. 
The following portions of the second edition are omitted from the 
third:—The genera Equisetum, Lycopodium, Isoétes, and Pilularia ; 
also a great number of the habitats of the commoner species, and a 
large portion of the critical remarks on the bibliography of the 
species. 
The following additions are made :—A short diagnostic character of 
every genus and species; a synonymic reference to all British and 
the more important continental describers ; and careful directions for 
the cultivation of every species. 
The following alterations have been made: —The history of each 
species is divided into heads, which are thus intituled :—Charac- 
ters; Synonymes, Figures, &c.; Geographical Range; Description; 
Varieties (if any); Culture; Economical uses: the details of the 
habitats of the rarer species are more minutely given than in 
the second edition, and those which are unsatisfactory, from any cause 
whatever, are inclosed in parentheses. 
The arrangement remains unaltered, but the author’s views of clas- 
sification are thus explained at length :— 
‘It is impossible for the candid mind to dwell for a moment on the 
fact that Britain produces only about one-fortieth part of the ferns 
already known as inhabiting the globe, without perceiving the im- 
practicability of arranging that fractional part in anything like a con- 
nected series. Select one British species, Capillus-Veneris, for 
instance, and we shall find that there are at least a hundred exotic 
species which approach it more closely than any that occur in 
Britain: therefore, assuming that two thousand ascertained ferns 
constitute a connected chain, it follows that in Britain a hundred 
links are wanting at that part of the chain where Capillus-Veneris is 
situate. There is still another mode of accounting for some of the 
monstrous gaps observable in the chain of species. The physical 
