Nature and development of plants . e of the ergot. 90. Forms with Broadly Opened Ascocarps.—The remainingorders of the Ascomycetes include genera in which the ascocarps DEVELOPMENT OF PLANTS 2 19 are broadly open and often associated with large masses of my-celium, thus forming a conspicuous stroma. 91. Order g. Pezizales or the Cup Fungi.—These plants arecharacterized by the formation of fleshy, leathery or gelatinouscup-like ascocarps that range in size from mere specks to formsfour or five inches in diameter (Fig. 156). The mycelium livesupon the humus in the ground or on decaying plants an
Nature and development of plants . e of the ergot. 90. Forms with Broadly Opened Ascocarps.—The remainingorders of the Ascomycetes include genera in which the ascocarps DEVELOPMENT OF PLANTS 2 19 are broadly open and often associated with large masses of my-celium, thus forming a conspicuous stroma. 91. Order g. Pezizales or the Cup Fungi.—These plants arecharacterized by the formation of fleshy, leathery or gelatinouscup-like ascocarps that range in size from mere specks to formsfour or five inches in diameter (Fig. 156). The mycelium livesupon the humus in the ground or on decaying plants and ap-parently in this and the next order frequently develops the asco-carps directly without a reproductive process. In Pyronema,however, Harper has shown that reproductive organs are formedthat are more suggestive of those of the red algae than was thecase in the blue moulds and downy mildews previously female gametangium has a long tubular outgrowth thatcurves over and becomes closely applied to the male (Fig. 157,. Fig. 157. Sexual reproduction of one of the cup fungi, Pyronema: A,the flask-shaped female gametangium, 0, is seen in various stages of fusionwith the male gametangium, an. B, the gametospores, g, germinating andforming branching hyphae which bear the asci, as. These asci are asso-ciated with hyphae or paraphyses, p, that arise from the mycelium. Theasci and paraphyses constitute the hymenium.—After Harper. A). The dissolution of the separating walls permits the fusionof the gametes, after which, the gametospore develops a numberof erect sac-like hyphae or asci (Fig. 157, B). Adjoining hy-phae of the mycelium grow up among the asci and around them. 220 LARGER FORMS OF ASCOMYCETES forming a cup-like structure resembling that shown in Fig. section through one of these cups reveals the asci intermingledwith hyphae, also called paraphyses, in the form of a layer orstratum. Such an association of spore-bearing organs and para-physes is called a hy
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