21 
reproductive organs are so well known—it seems to me that 
Lichens would still remain distinct and apart as a class by them- 
selves. The only change would be that Lichens must be considered 
less perfect plants than they had previously been thought to be by 
lichenologists, and it might entail some alteration in the classifica- 
tion of certain genera. But, except in a few imperfect species, the 
mode in which the gonidia first make their appearance in the 
thallus is totally opposed to the view that they are extraneous 
bodies, and I hold, with Dr. Nylander, that it is more likely to be 
true that the so-called algze are imperfect states of Lichens, than 
that a Lichen should consist of two distinct plants. 
But interesting as is this subject, I must leave it, as it is necessary 
to say a few words on those organs which produce the young 
germs of new individuals, and so preserve the species from gener- 
ation to generation. 
Every individual plant, from the time of its maturity to its decay, 
not only spends its energies on obtaining food for its own nourish- 
ment, but makes preparation for the continuance of its species 
after its own death, and each is fitted with organs necessary for 
this distinct function. In flowering plants two organs have been 
long known whose co-operation is necessary for the production of 
perfect seed, but it is only recently that the corresponding parts 
have been discovered in those tribes which do not bear flowers. 
Even now there are many plants in which after the most careful 
search they have not been discovered, but, as time goes on, the 
number of these constantly diminishes, and doubtless it will ulti- 
mately be found, that those which prove to be quite destitute of 
them are nothing more than imperfect states of other perfect 
plants. 
In Lichens the two organs of reproduction seem to be certainly 
identified, though the precise manner of their action still requires 
further investigation. 
Of the two, one has been long known, being often the most 
conspicuous part of the plant it belongs to. This is the apothecium, 
whose varied external shape among crustaceous Lichens I have 
already briefly sketched, 
