258 DIVISION II,—COURSE OF DEVELOPMENT OF FUNGI. 
and had termed their receptacles or the organs that carried them spermogonia; but 
it was shown by further observation that these cells were germinating spores or 
gonidia, and that their receptacles should be termed gonidiophores or pycnidia, Of 
a similar kind were the gonidia of Claviceps and other forms mentioned in Tulasne’s 
Carpologia, which germinate very readily. As these observations multiplied, the 
question naturally arose whether there really are spermatia which are absolutely with- 
out the power of germination, or whether the absence of germination in the alleged 
cases did not arise from defects in the mode of conducting the experiments, since 
some spores only germinate under fixed conditions, and the conditions may not 
always have been properly secured in the artificial cultivation of the plants. A work 
of Cornu? endeavours to give an answer to this question, and a further answer is to 
be found in Stahl’s treatise on Collema which appeared almost at the same time. The 
two are very different. 
Stahl’s work shows that there are spermatia which are not spores but fertilising 
organs, and describes the mode of fertilisation and the organ to be fertilised (see 
above on page 211). It does this, it is true, in a limited number of cases only; but 
what is known of the rest of the Lichen-fungi, and is not disputed by Cornu, proves 
further that by far the larger part of them possess spermatia which show no more signs 
of germination than those of the Collemeae, and that these spermatia are homologous 
with those of Collema. This is sufficient to distinguish the spermatia and spermogonia 
from spores and their receptacles in this long series of cases, even though nothing 
certain is yet known as. to the function of most of these spermatia. That exactly 
the same condition of things is to be found also outside the group of Fungi which form 
Lichens, is evident from the case of Polystigma described above on page 215. 
Cornu, on the other hand, simply does not allow that the spermatia are special 
organs, but would have them regarded as spores with the power of germination, 
while retaining the name which they have hitherto borne. His arguments for this 
view are not convincing. He saw first of all the ‘spermatia’ of certain species, which 
hitherto perhaps had been considered to be incapable of germination or had not been 
examined (for example those of Massaria Platani), produce germ-tubes when 
sown in nutrient solutions; a few more therefore to be added to the previously 
known cases of pseudo-spermatia. He also saw other known spermatia, those, 
for instance, of Stictosphaeria Hoffmanni, Tul. and Valsa ambiens, Tul., undergo 
changes of form, also in nutrient solutions, and swell up, but without showing further 
signs of germination. He gives no other new facts; the cultivation of the spermatia 
of Lichens gave him only negative results, and he can scarcely be said to have 
advanced the subject even in a single minor point. His treatise was published 
before the results of Stahl’s profound investigations were given to the world. 
From the facts which have been established we now know of spermatia or 
spermogonia in certain species or genera as organs with a definite function different 
from that of spores. We can also form a plausible view as to the homology of these 
bodies with the antheridial branches or functioning antheridia in other species which 
have no spermatia, as was attempted to be done above on page 231. Lastly, we are 
acquainted with a large number of species in which the homology of the spermatia 

1 Reproduction d. Ascomycétes (Ann. d. sc. nat. ser. 6, III) 
