CHAPTER V.—COMPARATIVE REVIEW.—-BASIDIOMYCETES. 329 
host, and a mycelium which spreads widely in the part of the plant which it attacks, 
deforming it more or less, and producing the basidial layer directly from its hyphae. 
The basidia are as usual club-shaped, and abjoint four fusiform spores. The spores 
divide as soon as they are ripe by transverse walls into four cells, and the two end- 
cells germinate at the expense of the protoplasm of the other two as soon as they 
reach a moist surface. If this is the surface of a young foliage-leaf of Vaccinium, 
the germination consists in the putting out of a tube, which at once grows through 
the young epidermis into the inner tissue of the leaf and there developes a mycelium. 
The mycelium forms the hymenium which bears the basidia directly; the time 
required in plants cultivated artificially is about 14 days from the sowing of the spores. 
If the spores germinate on some other substratum not so favourable as the leaf of 
Vaccinium, the germ-tube after attaining a short length begins to sprout and pro- 
duces rather elongated fusiform sprout-cells which sprout only at their extremities. 
The formation of sprouts may be repeated many times. Brefeld saw it continue for 
a year in specimens cultivated in nutrient solutions, and the power of production 
appeared to be unlimited. It can scarcely be doubted that the sprout-cells can give 
rise to a mycelium like that of the primary spores in suitable substratum ; but this has 
never been actually ascertained. 
The development of the Tremellineae, the species of Dacryomyces for example 
especially, would appear from the investigations which have been made to be the same 
as in Exobasidium. I refer partly to the statements of Brefeld!, partly to an 
unpublished series of researches conducted by Klebs. A mycelium is developed from 
the germinating basidiospore under suitable conditions of nutrition, and the branches 
from the mycelium combine to form compound sporophores which produce new 
basidia. Under different conditions, not in all cases exactly defined, the germ-tubes 
which proceed from the spores remain short and abjoint (successively ?) small secondary 
spores or develope by sprouting. We shall return to these phenomena in a subsequent 
page. There is moreover a further point’ of agreement between Dacryomyces and 
Exobasidium; the ripe basidiospore at the time of abjunction divides by transverse 
walls into short disc-like cells, daughter-spores, which are usually four in number, 
but each of these is capable of germination in Dacryomyces in one of the forms 
stated above. In other Tremellineae the basidiospores do not divide or they divide 
in a different and peculiar form. \ 
We are acquainted with the whole of the life-history of the Hymenomycetes 
proper in Typhula and species of Coprinus through the researches of Brefeld; in 
Agaricus melleus through those of R. Hartig and Brefeld; in Crucibulum and Cyathus, 
genera of the Nidularieae, from the labours of Eidam and Brefeld, and in Sphaerobolus 
from those of E. Fischer. 
The germinating spore of Agaricus melleus and Coprinus stercorarius puts 
out a germ-tube, which in all the Coprini is swollen into a vesicle at its point of origin ; 
the germ-tube developes directly into a mycelium and the compound sporophores are 
formed directly on the mycelium from the ramifications of the hyphae. No organs 
beside those described in the preceding pages, which can even be supposed to have 
any connection with the propagation of the plant, nor any rudiments of them, have 

” Hefepilze, p. 198. 
