Sketch of the Class Fungi. 



235 



semble them are usually found, but in which no spores are developed ; 

 these are called paraphyses. It is very probable that these are only 

 abortive asci ; they are found in Lichens, Byssacea and Hymenomy- 

 cetes ; we have mentioned also their presence in Pyrenomycetes. 

 Corda has observed and figured in Geoglossum hirsutum (Ic. Fung., 



ii. p. 35. t. 15. f. 124. 4. g, g.) a third kind of utricles fashioned like 

 the asci, but containing instead of spores irregular granules floating 

 in a very fluid mucilage. The ascomorphic cells, in consequence of 

 their great analogy in form and structure with the anthers of Mosses 

 (antheridia, Bisch.), seem to him to be destined to perform here the 

 functions of those organs, viz. to fecundate the spores. The same 

 mycologist has also remarked that the hymenium of the genus Agy- 

 rium is covered, like the proligerous disc of Lichens, with a compact 

 layer of cells, between which there are very visible vacant spaces. 

 This is, I think, very improperly termed proligerous disc, for it ap- 

 pears rather to be due to the remains of a kind of veil. In Agyrium 

 rufum we find instead of paraphyses a cellular tissue analogous to 

 that of the placentary or subhymenial tissue, between the cells of 

 which the asci are seated. 



Amongst Discomycetes there are genera and species in which the 

 asci are invariably fixed upon the receptacle, and others in which at 

 a certain period they are normally detached, and are discharged to- 

 gether with the spores which they contain (Ascobolus, Lachnella). 

 These organs are variable in form, but within certain limits. They 

 assume every form between that of cylindric and rhopaloid. Fries 

 calls them moniliform in his genus Orbilia, with which I am not ac- 

 quainted. 



The sporidia (or spores) are much more variable than the asci. 

 Thus they are spherical, ovoid, oblong, elliptic, much elongated and 

 obtuse at either end (baculiform), as in Propolis and Spathularia, or 

 else acute (fusiform, acicular), as in Geoglossum. As regards struc- 

 ture, they consist of a single cell, or else they are divided transverse- 

 ly, as in Geoglossum and Cryptodiscus, or at the same time longitu- 

 dinally and transversely, as in Melittosporium; in many cases by septa, 

 which render them plurilocular or compound. Their normal num- 

 ber varies between four and eight, but this number is always even. 

 They are formed, like those of other families, of a thin, elastic, trans- 

 parent episporium, whose cavity is filled, according to Corda, with a 

 white, limpid, hyaline, gelatinous substance, in which are suspended 

 some drops of an oily matter. He has followed and described (/. c. 



iii. p. 39) the morphosis of these organs in Peziza Acetabulum ; we 

 can only refer the reader to the passage. At the maturity of the 

 fungus, the sporidia in many species are ejected forcibly from the 

 asci by a sort of contractile power in these organs, in order to their 

 being dispersed in the air in the form of smoke or a cloud. This 

 dispersion of the sporules takes place at intervals, so that the ascus 

 empties itself completely by several successive jerks. This must 

 take place by a pore in the summit of the ascus, though the micro- 

 scope has not yet proved its existence. All the genera of the family 

 do not present the phenomenon just mentioned, nor all the species 



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