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themselves alone no more serve for propagation than the hyphae 
from the pileus or stalk of an Agaric, while it is highly 
improbable that they could acquire this faculty by interposition 
of a foreign algal. On the other hand, he argues it is much 
more conformable to nature that the gonidia, as self-developed 
organs of the lichens, should, like the spores, enable the hyphae 
proceeding from them to propagate the individual. This we 
believe to be the true doctrine concerning the relation of the 
gonidia to the hyphae ; and when the new theory has had its 
brief, if brilliant day, will no doubt be generally accepted. 
But apart altogether from these considerations, there remains 
another argument, which of itself is sufficient to show, whatever 
the connection in other respects between these two elements 
may be, it is certainly not that of a “ fungus” with algal- 
colonies or lichen-gonidia. For Schwendener’s master parasite 
turns out to be no fungus after all, as has clearly been shown 
by JNylander, in “ Grevillea,” ii. p. 147, note : “ The anatomical 
filamentose elements of lichens are distinguished by various 
characters from the hyphae of fungi. They are firmer, elastic, 
and at once present themselves in the texture of lichens. On 
the other hand, the hyphae of fungi are very soft ; they possess 
a thin wall, and are not at all gelatinous, while they are 
immediately dissolved by the application of hydrate of potash, 
&c.” This well-marked and essential distinction between the 
two, which observation amply verifies, at once effectually 
demolishes the fungal part of the Schwendenerian hypothesis 
So much, then, for the two leading principles upon which the 
new theory evidently rests. The three other minor considera- 
tions adduced by the author in its support, as quoted by us 
above, are disposed of by Von Krempelhuber, 1. c., in a very few 
words. To the second, he replies that this difference of reaction 
is of no importance, since the membranes of the thecae 
originating from the hyphae give the same reaction as that of 
the gonidia-membrane. To the fourth, he replies, that though 
the observations of Tulasne, &c., did not entirely succeed in 
directly establishing the development of the gonidia from the 
hyphae, still, from their regular appearance upon the latter, the 
probability that this was their origin cannot reasonably be 
denied. And to the last consideration he replies that the pre- 
sence of gonidia is not the only distinguishing feature between 
even the lowest lichens and such fungi (. Pyrenomycetm ) as show 
an agreement in their fructification. But besides these par- 
ticular objections to the hypothesis, there are various other 
more general ones, of equal validity, which have been adduced. 
Of these the two principal have reference to the nutrition and 
the distribution of lichens. With respect to their nutrition, 
Nylander, “ Obs. Pyr. Or.,” 1. c., has stated that u it is around 
