14 FUNGI. 
genera, must, however, be considered as connecting Trichogastres 
with lichens, and the question cannot be considered as satis- 
factorily decided till a series of experiments has been made on 
the germination of lichen spores and their relation to free alge 
considered identical with gonidia. Mr. Thwaites was the first 
to point out* the relation of the gonidia in the different sections 
of lichens to different types of supposed alge. The question 
cannot be settled by mere @ priori notions. It is, perhaps, 
worthy of romark that in Chionyphe Carteit the threads grow 
over the cysts cxactly as the hypha of lichens is represented as 
growing over the gonidia. 
Recently, Dr. Thwaites has communicated his views on one 
phase of this controversy,f which will serve to illustrate the 
question as seen from the mycological side. As is well known, 
this writer has had considerable experience in the study of the 
anatomy and physiology of all the lower cryptogamia, and any 
suggestion of his on such a subject will at least commend itself 
to a patient consideration. 
“ According to our experience,” he writes, “I think parasitic 
fungi invariably produce a sad effect upon the tissues they fix 
themselves upon or in. These tissues become pale in colour, 
and in evcry respect sickly in appearance. But who has’ ever 
seen the gonidia of lichens the worse for having the ‘hypha’ 
growing amongst them? ‘These gonidia are always in the 
plumpest state, and with the freshest, healthiest colour possible. 
Cannot it enter into the heads of these most patient and ex- 
cellent observers, that a cryptogamic plant may have two kinds 
of tissue growing side by side, without the necessity of one 
being parasitic upon the other, just as one of the higher plants 
may have half a dozen kinds of tissue making up its organiza. 
tion? The beautifully symmetrical growth of the same lichens 
has scemed to me a sufficient argument against one portion 
being parasitic upon another, but when we see all harmony and 
robust health, the idea that one portion is subsisting parasitically 
upon another appears to me to be a perfect absurdity.” 
* “ Annals and Magazine of Natural History,” April, 1849. 
+ In ‘Gardener's Chronicle” for 1873, p. 1341. 
