CHAPTER V.—COMPARATIVE REVIEW.—-ASCOMYCETES, 245 
and some others. Ripe and “ripening perithecia may in these plants stand side by 
side on the same mycelium or stroma with developing gonidiophores. 
It is scarcely necessary to remark that the succession of events does not always 
proceed in these examples with perfect regularity; and the instance of Peziza 
Fuckeliana described above on page 224 shows that considerable deviations from it 
may and do occur. 
As regards the point of origin of the gonidiophores and their arrangement and 
structure, it would seem that they occur in particular species in the ascocarps them- 
selves, like the doubtful spermatia noticed on page 242. According to Berkeley’ 
single paraphyses are found between the asci in Sphaeria oblitescens B. et Br., in which 
one or two of the cells are enlarged into somewhat elongated septate ‘spores;’ the 
terminal cells of such paraphyses in Dothidea Zollingeri, Berk.’ are like simple 
ellipsoid spores. Berkeley* makes a similar statement in the case of a species of 
Tympanis and for Lecidea Sabuletorum * or an allied form; but these points require 
re-examination, as Tulasne has intimated®, because we are still ignorant of the 
qualities of these spore-dike bodies. 
Putting aside these few doubtful and possibly exceptional cases, all gonidial 
formations conform to the examples described above which have been thoroughly 
examined. The following special forms may be enumerated :— 
(a) Free filiform gonidiophores; often very characteristic in their conformation, 
as in Penicillium, Eurotium, Erysiphe, &c., and in such cases formerly assigned to 
established form-genera. Thus species of Hypomyces were assigned to the form- 
genera Verticillium, Sepodonium, and Mycogone of the old descriptions, and 
Fusisporium Solani®; species of Nectria to Fusisporium and Spicaria of the old 
descriptions, and many other cases might be cited. To these may be added some 
other forms, in which the distinction between gonidia and gonidiophores on the one 
hand and portions of the mycelium on the other is less sharply defined, and may even 
be arbitrary in each individual instance up to the extreme cases in which each cell 
of a hypha or a hyphal strand first performs the part of a mycelium and then 
assumes the characters of a spore. The latter is in extreme cases naturally 
termed the formation of resting mycelium and has been elaborately studied by Bauke 
and Zopf, especially in saprophytic Pyrenomycetes, though older observers often men- 
tioned it incidentally. It occurs in old and specially in starved mycelia for example 
of Pleospora, Fumago, and Cucurbitaria, in which the cells of the mycelium 
acquire thick and usually brown walls, store up reserve food material, and pass into a 
dormant state, and subsequently under suitable conditions germinate as spores. 
Changes of form, especially swelling of the individual cells into a spherical shape, may 
or may not accompany the changes which characterise the state of rest, and hence the 
resting states differ in very various degrees from the vegetative mycelial forms. 

X Ann. Mag. Nat. hist. ser. 3, III, p. 373, t. XI, 32. 
2 Hooker’s Journ. III (1844), p. 336. 
-® Introd. Crypt. Bot. p. 244. 
* See Ann. Mag. Nat. Hist. ser. 2, IX, and Crypt. Bot. p. 391. 
5 Mem. ». les Lichens, p. 110. 
© Reinke u. Berthold, Die Zersetzung d. Kartoffeln durch Pilze, 1879. 
