38 ON THE BLEACHED WOOD 
abrasion of gravel, as in several specimens which have been exposed to 
such abrasion from one to forty years. 
It is time however to make such especial observations as occur to 
me respecting the two pieces of wood brought home by Captain Peuny. 
One thing at least appears tolerably certain, now the nature of the ve- 
getation on the Elm is ascertained, that whatever length of time it may 
have taken to bleach the surface to the extent to which it is now 
bleached, the vegetation on it was that of the summer in which it was 
found. From observations on that and similar productions here, they 
appear to be Fungi of but short duration, at least in such a state of per- 
fection as that in which they appear in point of fructification on the 
Arctic wood. It is very possible that for a certain limited time a fresh 
succession of specimens might arise, but those on the Arctic wood are 
all evidently in the same stage of growth, and it is scarcely probable 
that they can have retained through the temperature of an Arctic 
winter their delicate naked spores in a state of perfection. It is pos- 
sible, indeed, that on a surface annually abraded a new crop of the 
same Fungus might spring up every year; but this would not apply to 
the split surface, on which the Fungi are in the same condition as on the 
other surface. A single perithecium of a different species was found in 
a crack, but little is to be concluded from this, as the crack might take 
place at very uncertain periods of time. In the same crack I also found 
the same species as that which occupies the bleached fibres; and it is 
worthy of remark, that in Oak piles exposed to weather on the coast 
for forty years, as observed by Sir J. Richardson, young immature 
Spherie, with their nucleus still in a Sclerotioid state and quite devoid 
of asci and sporidia, are plentifully produced on the fissured surface. 
On the whole then, as far as the evidence of the Cryptogamic growth 
affects the question as to the time of exposure of the plank, it is cer- 
tainly, as far as judgement may be formed from such growth in our la- 
titude, in favour of a recent exposure; but this evidence is to be coun- 
terbalanced by the experience of those who have had an opportunity of 
observing the very slow effect of climate on wood exposed in those 
countries*. 
And this is strongly confirmed by the other piece of wood mentioned 
* See that part of the Report relative to the blade of an oar now at the Admiralty, 
which had been drifting since 1833, the last time the whaler whose name it bears 
was in Baflin's Bay. Among other articles left behind by Sir John Franklin's party 
