Now this dual-Lichen hypothesis has been accepted as true by 
some very eminent botanists both at homo and abroad, but it lias 
also been opposed and denied by otlier botanists of equal standing, 
both foreign and British. As far as I can understand the theory, 
tho Algie referred to by Schwendener are the gonidia or green 
bodies which are ultimately embedded in the substance of tho 
thallus of tho Lichen, whilst the Fungus, the parasite, includes all 
tlio rest of tho plant, and tho hyplue, or minute branched filaments 
surrounding tho gonidia, are tho means by which tho Fungus draws 
its nourishment from the Algio ; but there seems a difference of 
opinion as to tho facts, between tho opponents and tho defenders of 
tho theory, for whilst Bornet, who accepts it, says, that the hyplue 
never produce gonidia, J. Muller, who rejects it, says, that tho 
hyphro do produce micro-gonidia, which ultimately become tho 
gomdia themselves; and according to some recent observations of 
his on a Brazilian species of tho genus Ctvnogoninm^ the large green 
tubes which contain tho gonidia narrow suddenly into "slender 
capillary tubes, without any discontinuation of tho cavity between 
tho largo tube and the capillary portion : this narrow portion ho 
considers perfectly conformable to tho slender hyphal tubes of the 
theoretic Fungus. Examined microscopically by high powere, this 
slender portion of tho tube showed clearly tho micro-gonidia, or 
gonidia in their preliminary state, under their form, size, and normal 
arrangement, and in this respect there is a conformity between the 
narrow part and tho hyphal enveloping tubes of the encased 
filaments. “It follows that one and tho same cell — in the one 
case enlarged and bearing gonidia, should have been the theoretic 
Alga— while in the other case remaining narrow, and containing 
tho micro-gomdia, it should have been the theoretic Fungus, thus 
proving in the most absolute manner the falsity of the theory, that 
one and tho same cell may at the same time belong to two classes of 
vegetation.” 
Of course I am in no position either to confirm or to deny 
iAIuller’s observations; I can only say, that if they should eventually 
be confirmed by other observers, they amount to something very like 
a simple reduct to ad absurd inn of the Schwendenerian hypothesis; 
