260 DIVISION II.—COURSE OF DEVELOPMENT OF FUNGI. 
pycnidia and similar formations, and we must not here enter further into the details of 
the subject than the reader can at any time do for himself by comparing the examples 
described in the preceding pages. But we may just observe that it is possible that 
metamorphosis may be found in cases where it has been quite unsuspected. The 
hymenium which has already been repeatedly described is found on the young stroma 
of the Xylarieae, Claviceps, Epichloe, &c. either before or together with the first 
appearance of the sporocarp, and gives off small cells, which in structure, origin, 
and size might be spores (gonidia) or spermatia. There can be no doubt that they 
are homologous in all these species. They were called gonidia in a previous page, 
because they germinate in Claviceps and Epichloe, and in Poronia and Ustulina 
among the Xylarieae ; but, as far as we know, they do not germinate in Xylaria—a fact 
which may be added here to complete our former observations on the genus. These 
phenomena find their explanation in the hypothesis here proposed, and may 
therefore be brought forward in support of it; but it is obvious that the hypothesis 
is not hereby made a certainty. 
In conclusion we must recur again to the objects which were included in page 242 
under the name of doubtful spermatia. The word ‘ doubtful’ must still be repeated 
of many of them, for we possess only brief accounts of them, and portions of these 
are disputed. I confine myself therefore to the cases of Sordaria, Chaetomium, and 
Sclerotinia, which we know more in detail through the labours of Zopf and Brefeld. 
Here, according to these observers, the organs in question agree as much in their 
characteristic development and structure as in their power of germination under the 
conditions to which they were submitted, and they have no other function, as far as 
could be ascertained, than that of spores. They are therefore organs whose 
function is unknown to us. It is osszble that they have no function at all; at any 
rate as they do not function as sexual or otherwise reproductive organs, they can 
scarcely have any important duties to fulfil, for they are usually few and small; and 
if the case is otherwise in the specimens of Sclerotinia tuberosa grown by Brefeld, we 
must not forget that in this instance the Fungus was growing under conditions quite 
foreign to its usual circumstances. Having regard to the known facts and to the 
analogies and homologies which may be applicable, there is the alternative proposed by 
Zopf for the determination of these bodies, that they are either functionless spermatia, 
or spores or gonidia not capable of germination. This is not a matter of indifference 
in reference to the question of the homology. But gonidia without the power of 
germination, according to all trustworthy data, are things which nothing but 
extreme necessity can allow us to assume; and in the case of the Chaetomieae, 
where, according to Zopf, almost every cell of the mycelium may becomea gemma 
or gonidium with power of germination, and in Sclerotinia Fuckeliana with its 
characteristic and highly reproductive gonidiophores, it would be an absurd thing 
that such well-furnished appliances should be occupied solely in producing sterile 
gonidia. But if we suppose these bodies to be homologous with spermatia, the 
whole matter becomes intelligible from the points of view which have now been 
discussed. Only one objection has been brought forward to this view. Brefeld? 
calls attention to the difficulty of accounting for the concurrence in ‘Sordaria’ of 

! Schimmelpilze, IV, p. 143. 
