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Fig. 2.14Diagrammatic representation of some fruiting structures of Ascomycota. (a) A single ascus containing eight
ascospores which, at maturity, will be shot forcibly through the narrow apical pore. (b) A cup-shaped apotheciumcon-
taining many asci interspersed with sterile “packing” hyphae (paraphyses). The paraphyses help to laterally constrain
the developing asci so that they project beyond the surface of the cup to release their spores. (c) A cleistothecium
(closed ascocarp) such as that of Eurotium, the sexual stage of some Aspergillusspp. The asci, each with eight asco-
spores, are released when the cleistothecium wall breaks down at maturity to release the ascospores.

Fig. 2.13(a) A developing perithecium of Sordaria
macrosporawhich, at maturity, will have a pore at its tip
to release the ascospores. (b) Several asci in different stages
of development within the perithecium; each ascus con-
tains eight ascospores, about 20mm diameter. (Courtesy
of N. Read; from Read, N.D. & Lord, K.M. 1991 Experi-
mental Mycology15, 132 –139.)

(a)

(b)

FB4eC02 04/20/2005 02:52PM Page 28

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