
162 THE BRITISH FERNS. 
When the plants now referred to Lastrea and Polystichum were 
included in Aspidium they bore the English name of Shield Fern. 
It is however objectionable to use the same appellation for different 
genera, and as the old name of Shield Fern is properly applied 
to the more typical group Polystichum, we have proposed in the 
Handbook of British Ferns and adopted here, for the Lastreas, the 
equivalent name of Buckler Fern. 
The seven or eight British species of Lastrea are distributed by 
Mr. Newman among four genera, of which two originate with himself. 
Thus, for Lastrea Thelypteris he proposes Hemesthewm ; Lastrea 
montana, better known by the more modern specific name Oreopteris, 
is left to represent Lastrea, of which it is assumed to be the type 
species; while for Lastrea Filiz-mas, Schott’s name Dryopteris is 
adopted; and for Lastrea cristata and its allies, Lophodium is 
imposed. These proposed groups do little more than represent 
specific differences. 
The species referred to this genus admit of being distributed into 
five sectional groups, of which two are represented by British species. 
These are:—§ Dryopteris, and $ Thelypteris, the former having the 
veins forked or pinnate, the anterior branch or venule being fertile 
and the sori medial or subterminal, covered by distinctly reniform 
indusia, and being represented by Lastrea Filiv-mas and Lastrea 
dilatata; the latter, having the veins forked, both branches or. 
venules bearing sori, which are covered by irregular fugacious in- 
dusia, and represented by Lastrea Thelypteris and Lastrea montana. 
The remaining sections are :—§ Pycnopteris, with pinnate subclavate 
veins, and several series of sori, infra-medial on both anterior and 
posterior venules, represented by the Lastrea Sieboldii of Japan; 
$ Monophlebia, in which the veins are usually simple, and the 
sori medial or subterminal, represented by the Lastrea patens of 
. South America; and $ Camptodium, in which the veins are pinnate, 
and the sori terminal or medial on both anterior and posterior - 
venules, represented by the Lastrea pedata of the West Indies. 
The name of the genus in its original form (Lastrea) was given 
by Bory de St. Vincent, in honour of M. Delastre of Chatelleraut, 
a zealous botanist and microscopist. 了 Presl in adopting it and giving 
it a new application, writes it Lastrea. 

