T 
438 
and we should then have to fall back on the previously accepted 
theory, that the gonidia are reproductive bodies, belonging to the 
Lichen proper; and that, as Dr. Cooke considers, there is “neither 
Alga nor Fungus, but only Lichen,” and that Lichens form an 
independent class of plants, having some of the characteristics of 
the other two classes. Be this as it may, the observations of 
Herr Brandt and Mr. Geddes seem to me very clearly to prove the 
fact of the “ life in common,” or “ consortism,” of very low classes 
of animals and plants, and to open to us a new chapter in that book 
of Nature which we are all so anxious to study; and if I have been 
so fortunate as to interest you in this subject, or, better still, to have 
set you seriously thinking on the very curious mutual relations by 
which these organisms, one living within the other, are supported 
by each other’s products, I must beg you to remember, that nothing 
of what I have said to-night is original, and that I have merely used 
“scissors and paste” on other men’s work, to bring before you 
something comparatively new. 
