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FERNS : BRITISH AND FOREIGN. 
being no doubt latent in tbe soil used for filling tbe 
pots. To avoid this it is advisable to bake tbe soil 
before using, and to bring it again to its proper moist 
state by tbe use of water that bas been boiled. 
It is said that spores retain their vitality for a 
number of years ; in my experience I have no direct 
proof of this ; but several remarkable instances of 
plants making their appearance without the spores of 
the species having been sown, or even an Herbarium 
specimen having been seen in this country. In the 
instance of Lomaria Pater semi, a species originally 
discovered in Tasmania, which spontaneously made 
its appearance at Kew in 1830, only one specimen 
was at that time said to be in the possession of Mr. 
Brown, at the British Museum, which I never saw ; and 
Allan Cunningham informed me that he never found 
the plant, and was very much surprised when he saw 
it growing at Kew. This in time gave specimens to 
many Herbaria, and living plants to botanic gardens. 
A similar instance was that of Doodia blechnoides, 
which made its appearance at Kew in 1835. Other 
instances might bo quoted, such as the appearance of 
Asplenium stipitatum, of which two plants spontaneously 
made their appearance about twenty years ago, and I 
at first supposed they had originated from the spores 
from a specimen in my Herbarium of a Luzon plant 
named by me Neottopteris stipitata; but in time it 
became evident that the two plants were quite distinct 
from it, and, like the Lomaria and Doodia, I had never 
seen native specimens. By what means the spores that 
produced these plants came to Kew it is impossible to 
say. In 1829 I found a plant of Geteracli officinarum 
growing in a crevice of masonry on one of the 
