T RICHOMA NES. 
from one to three inches long, somewhat ovoid in shape, the upper ones becoming gradually 
smaller ; they are deeply cut into oval or oblong pinnules, which are themselves cut into linear 
bluntish teeth. A dark firm vein runs through each of these divisions, and is the more con- 
spicuous on account of the pale transparent green of the foliaceous portion of the frond ; so 
striking indeed is it, that the frond has been described as consisting of a series of three or 
four times branched rigid veins, bordered throughout by a thin pellucid wing. These veins 
end at the apex of the segments, when the fronds are barren ; but in fruit-bearing specimens 
they are produced beyond it into a bristle-like point, to the appearance of which the name 
“ Bristle-fern ” is due. This forms a receptacle, upon the base of which is situated the small 
roundish cluster of sporangia ; this is surrounded by a cup-shaped involucre, formed by the 
indusium and frond-segment, which are very similar in texture; the cup is open at the top, 
which is very slightly two-lobed. The bristle-like receptacle projects a variable distance beyond 
the edges of the cup, as shown in the figure at the end of this article. The sporangia 
are sessile, pear-shaped, and provided with a complete transverse ring. The spores are pale, 
somewhat greenish in the centre, and very minutely granulated. The fronds in the Irish 
plant are three years in arriving at maturity ; when growing in a moist situation, they 
will remain beautifully green for many years, provided that the fruit be not matured ; in 
the latter case, however, the fronds change colour and begin to wither away as soon as 
the spores have been shed. Mr. Andrews, who studied the plant in its native Irish localities, 
is of opinion that the fructification is only matured in warm dry seasons, and that even 
then it is comparatively rare, the sporangia being duly formed, but failing to attain 
sufficient ripeness and elasticity to discharge the spores. In Madeira the fronds are stated 
to be fertile in their second year, and in Mexico they bear fruit the first year of their 
existence. 
It was at one time thought that we possessed in Ireland a second species of Trichomanes, 
for which the name T. Andrewsii was proposed by Mr. Newman, in commemoration of its 
discoverer, Mr. Andrews ; this, in its most characteristic state, differs from T. radicans in having 
narrower and proportionately longer fronds, a scarcely tomentose rhizome, and receptacles 
produced very much beyond the involucres. But however different in extreme examples, it 
has been found that these characters are not of permanent value, intermediate specimens 
between the two forms being readily found. T. Andrewsii was originally found at Glouin 
Caragh, Co. Kerry, and subsequently at Killarney. 
The Killarney Fern has been reported of late years from various localities in England. 
Whether it is to be regarded as an introduced plant is perhaps open to question, but there 
can be no doubt that it grew in Yorkshire less than a century ago, and that it had then been 
known to grow there more than fifty years. In the third edition of Ray’s “Synopsis” (1724), 
this fern is mentioned as having been found by Dr. Richardson “ at Belbank, scarce half a 
mile from Bingley, at the head of a remarkable spring, and nowhere else that he knows of.” 
There is no ground for the supposition that some other plant was mistaken for the Trichomanes, 
inasmuch as there is a specimen in one of the volumes of the Sloane Herbarium (vol. cccii., 
p. 66), in the British Museum, with a ticket appended in Dr. Richardson’s handwriting : — 
“ This beautyfull capilary I lately found in the moist and shady rocks nigh Bingley.” In the 
large herbarium of British plants contained in the collection of the British Museum there is 
also another specimen from the same locality collected by Hudson; and the following detailed 
account of the occurrence of the plant at Bingley is given in Bolton’s “ Filices ” : — First 
discovered by Dr. Richardson in a little dark cavern under a dripping rock, a little below the 
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