THE EUROPEAN BRISTLE FERN. 297 
nium marinum, which seems to like the situation tolerably. I have 
even tried Hymenophyllum tunbridgense, and H. Wülsoni ; neither of 
which lived past one year. The plant has never shown the least 
approach towards producing seeds, although I have seen many 
plants taken from the same locality (Turk Waterfall, Co. Kerry) 
which have fructified profusely.’ ” 
This instance of success, Mr. Ward goes on to state, is suggestive 
of one or two reflections of practical application. “We see, first, 
how possible it is to grow some plants in closed cases in even more 
than their native luxuriance. I believe that it would be very 
difficult, if not impossible, to find such a patch of Trichomanes as is 
above described, either in Ireland or any part of the world. The 
next reflection is, that, in obedience to well-known physiological 
laws, whenever the foliage of a plant is developed to a greater 
extent than usual, the tendency to produce fruit becomes propor- 
tionally diminished, and sometimes, as in the above instance, ceases 
altogether—not one frond out of the two hundred and thirty fructi- 
fying. It would be interesting to watch the effect of exposure to 
stronger light, and of a diminished supply of water. We further 
learn that Ferns, like other plants vary much as to their natural 
states, and that, in order to grow even the British Ferns in one 
case, it will be necessary to pay attention to their respective wants. 
* In order to grow all our Ferns under one roof, it would, of 
course, be necessary to fulfil their varying conditions of growth ; 
and this might be easily effected by building a model of some 
antique ruin, or by imitating some mountainous ravine, or other bit 
of natural scenery, with water trickling down from the elevated 
portion of the rock, and flowing out of the house in a continuous 
stream at the bottom. In such a house, without any artificial heat, 
our Ferns would attain a luxuriant growth, unimaginable by those 
who know them only under ordinary circumstances. Each Fern could 
be supplied with a proper base of earth or rock, and each could 
have the amount of light most suited to its fullest development. 
The Trichomanes might there revel on its Turk rock, and gladden 
the eyes of the beholder with its lovely fronds spangled with 
iridescent rain-drops. At the base of the rock, and extending to the 
margins of the central brook, the two species of Hymenophyllum, 

