318 
HYMENOPHYLLACE^. 
Adiantum-nigrum^ Lastrcea reciirva, &c. The apex of the frond 
is often lengthened very remarkably, but the lower pinnse almost 
invariably partake of a similar elongation. In lanceolate fronds, 
the lowest pair of pinnse are usually shorter than the second 
pair, the second shorter than the third ; and this character in 
Asplenium lanceolatum^ Lastrcea multijlora^ &c., remains unal- 
tered under any condition. Now the two Trichomanes, although 
less decidedly deltoid or lanceolate than the ferns I have cited, 
follow the same law, each preserving respectively its deltoid or 
lanceolate tendency under cultivation. 
Again there is a decided difference, as far as I can learn from my 
limited materials, in the involucres of the two plants. In the 
Killarney plant the involucre stands out distinctly from the mem- 
branous frond, and appears almost stalked, while in all my spe- 
cimens of the Glouin Caragh plant it is more or less united with j 
the frond by a continuous margin or wing ; this will perhaps 
become more evident from an inspection of the figures at page > 
320, which fairly express the differences observable in my spe- 
cimens from each station. Supposing that the deltoid and lan- 
ceolate fronds are constant in each plant, and that the exserted 
and partially imbedded involucres are also constant, I think | 
there can be little doubt that Mr. Andrews’s plant claims the rank ' 
of a species ; the extraordinary length of the receptacle, the less | 
divided state of the frond, and the less tomentose rhizoma, so 
ably pointed out by the Irish botanists, will furnish additional 
support of such a decision, although I scarcely like to take j 
either of these as a specific character. Still I hesitate to add a | 
species to our British Ferns unless possessed of more ample 
means for forming an opinion ; and I give to the plant the name 
of Andrewsii as a variety only, respectfully begging of subse- ’ 
quent describers, that snould their views coincide with mine, 
they will still allow the plant to bear the name of a naturalist 
to whose ardour and intelligence the science of Botany is under 
so many and such important obligations. i 
The cultivation of this beautiful fern has occupied the atten- ) 
tion of many botanists : I believe Mr. Mackay of Dublin, and | 
Mr. Ward of London, were the first whose efforts were attended ij 
with success. Mr. Ward possesses a plant which for many 'j 
k 
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