. Introduction to the study of fungi; their organography, classification, and distribution, for the use of collectors. Fungi. 62 INTRODUCTION TO THE STUDY OF FUNGI. in the Phycomycetes two bodies are formed, or two specialised cells come into contact, and the result is a zygospore, which is nearly always a resting spore, as a consequence of fertilisation. In the Discomycetes it is suggested that in its earliest stage the elements of the future cup, or receptacle, .become fertilised by contact with specialised filaments which represent antheridia. In the Perisporiaceae special processes are aff
. Introduction to the study of fungi; their organography, classification, and distribution, for the use of collectors. Fungi. 62 INTRODUCTION TO THE STUDY OF FUNGI. in the Phycomycetes two bodies are formed, or two specialised cells come into contact, and the result is a zygospore, which is nearly always a resting spore, as a consequence of fertilisation. In the Discomycetes it is suggested that in its earliest stage the elements of the future cup, or receptacle, .become fertilised by contact with specialised filaments which represent antheridia. In the Perisporiaceae special processes are affirmed to be emitted from two adjacent hyphae, which are supposed to become respectively oocysts and antheridia, and from their contact to result in the production of fertilised perithecia. In the whole of the Basidiomycetes no definite mode of fertilisation has been confirmed. And for the rest, we seek for evidence in vain. In Tilletia, a genus of the Ustilagineae,1 peculiar phenomena undoubtedly take place in the conjugation of promycelial spores, but this can scarcely be interpreted as an act of fertilisation. The facts are simply these: when the spore germinates it pro- duces a promycelium, a germ tube, which gives origin to bodies called primary sporidia, or, more properly, promycelial spores (Fig. 40). "A very remarkable feature about these 'primary sporidia' is that they almost invariably conjugate in pairs; that is, adjacent pairs become organically united by a short tube grow- ing from one and becoming blended with the other, thus placing the protoplasm of the two sporidia in direct communication. In some instances conjugation takes place before the primary sporidia break away from the promycelium. After conjugation a slender germ tube is formed, which receives all the protoplasm from the two united sporidia, and if developed upon the proper host plant, penetrates into its tissues and forms a mycelium, which in turn produces a new crop of resting spores. In some Fi
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