. A handbook of cryptogamic botany. Cryptogams. ^k. FiG. 273.—Agitricus dryophilus Bull, a, compound sporophore, longitudinal section showing the course of the hyphse, a very youn? complete specimen i'3 mm. in height, first begiiinings of pileus : b, older specimen with pileus 2*5 mm. in breadth : /, piece of a lamella (slightly magnified). (After de Bary.) sporophore : for example, Penicillium, though commonly simple, some- times produces tufts of sporophores formerly supposed to belong to a different fungus under the generic name of Coremium. Spores. The prevailing mode of spore-formation is
. A handbook of cryptogamic botany. Cryptogams. ^k. FiG. 273.—Agitricus dryophilus Bull, a, compound sporophore, longitudinal section showing the course of the hyphse, a very youn? complete specimen i'3 mm. in height, first begiiinings of pileus : b, older specimen with pileus 2*5 mm. in breadth : /, piece of a lamella (slightly magnified). (After de Bary.) sporophore : for example, Penicillium, though commonly simple, some- times produces tufts of sporophores formerly supposed to belong to a different fungus under the generic name of Coremium. Spores. The prevailing mode of spore-formation is by acrogenous adjunction. The terminal portion of the mother-cell or a special protuberance formed on it is cut off by a transverse wall, and this daughter-cell then drops off as a spore. The basidiospores of Basidiomycetes may be taken as an, example. Finely pointed processes are formed on the summit of the basid, and these swell into ball-like form at the apex. The globular body is then abjointed and set free as a spore. Series or chains of spores are successively formed in like fashion in Cystopus, Penicillium, Uredinese, &c. Spores are also endogenously formed within mother- cells—sporanges—and these are of two kinds, motile and non-motile. Examples of non-motile spores thus formed are to be found in Mucor, and in the ascospores of Ascomycetes. Such spores are either set free by the disappearance of the sporangial wall or by internal causes effecting their ejection. Motile spores or zoospores (swarm-spores) possess the power of moving freely in water by means of fine whip-lashes or cilia, and examples of these are to be found in the Saprolegniese and Perono- sporese, the groups presumably most nearly related to Algae. That the phenomenon of the production of swarm-spores is one nearly akin to that. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustr
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