308 PART IV. VEGETABLE TAXONOMY. 



or carpophores, which constitute the above-ground parts of the 

 Agarics, Puff-balls, Cup-fungi, etc., and the sclerotium, a com- 

 pact, hard mass of thick-walled hyphse, which serves as a resting- 

 stage in the development of some species, as the Ergot of Rye 

 and some others. 



The Fungi reproduce asexually by means of conidia or gonidia, 

 as they are also called. In some species, chiefly aquatic forms, 

 these are motile spores provided with cilia, but in most, they 

 are non-motile thick-walled cells, which become separated from 

 the parent hyphge in ways which are more or less characteristic 

 in the different groups. 



In all hyphal Fungi, the hyphse consist of two portions, the 

 vegetative, which ramify in the substratum, often forming tangled 

 felt-like masses of threads, called the mycelium, and the repro- 

 ductive, which come to the surface ; it is the latter which 

 produce the conidia. They may be borne on isolated filaments, 

 as in the Bread-mould (Penicillium), or on a carpophore, which 

 produces a spore-bearing hymenium. The common Mushroom 

 (Agaricus campestris), is an example of the latter, the plate-like 

 bodies or gills, on the under surface of the cap, constituting the 

 hymenium. 



In a large number of Fungi, including some of the most 

 highly organized forms, sexual reproduction is unknown. Doubt- 

 less in many it yet remains to be discovered, but there is 

 good reason to believe that in some the power once possessed 

 has been lost. This is believed to be true of the Basidiomy- 

 cetes — the group to which belong the Agarics, Polypori, Puff- 

 balls, etc. 



In other species, however, for example, Mucor, sexual repro- 

 duction takes place, as in Mesocarpus, by conjugation ; in still 

 others, as in Achlya and Peronospora, it takes place by the pro- 

 duction of oospores in a manner similar to that in the oosporous 

 Algae. In fact, we may regard these Fungi as degenerate para- 

 sitic or saprophytic forms of Algae analogous to the saprophytic 

 Ericaceae, and other chlorophylless flowering-plants. 



In other forms, as, for example, the Cup-fungi, an act of 

 fertilization precedes the development of the hymenium-bearing 

 carpophore, and is the stimulant cause of it. 



The more recent classification of Fungi distributes them into 



