THE LARCH CANKER 41 
. able period in the cavitics. The cavities usually, though 
so far as I can determine not invariably, connect with the 
outside air by irregular mouths, which are mere gaps in the 
mycelial cortex, and are not lined by specialized hyphae. 
Through these mouths the spermatia are forced out by the 
formation of numerous younger ones behind, and often 
remain in masses stuck together by a mucilaginous liquid 
which is exuded with them. 
These spermatia are quite functionless, and, as the name 
implies, are regarded as vestigial male cells. Many botanists 
now consider them to be functionless 
conidia. The reasons against this view are 
i shortly as follows. 
Firstly, they will not germinate. Massee 
(1902) describes and figures cells, which he 
considers to be conidia, germinating by 
normal germ tubes in the presence of 
sections of larch bark. But the cells 
which he describes are round and larger 
than spermatia, and bear an intimate 
resemblance to conidia of Penicillium sp., _ Fis. 19.—Ascus 
* .. which has dis- 
which grows commonly on the apothecia charged its spores. 
of Dasyscypha. Brefeld (1891), who also 
regarded these cells as conidia, states that Dr. Moller, working 
in his laboratory, found that they became slightly swollen 
when placed in a nutrient solution, but did not germinate. 
This incapacity for germination is normal in spermatia, 
whose only function is fertilization; but it is not easy to 
understand why conidia should ever become functionless in 
this way. 
Secondly, we know from the researches of Baur (1898), 
Darbishire (1900), Thaxter, &c., that in some Ascomycetes 
fertilization is still effected by means of spermatia. In 
other Ascomycetes fertilization by spermatia has been 
replaced by fecundation by a hypha in proximity with the 
female organ, or by the fusion in pairs of the nuclei in this 
organ. Probably one of these methods obtains in Dasy- 
scypha, but the investigation of this point is outside the 
