ASCOMYCETES. 



[ '9 ] 



ASCOMYCETES. 



and have a flocculent niycelium, bearing 

 little columnar bodies terminating in a thick- 

 ened head — the sporange, which is a kind of 

 hood falling ofl" at matinitv. The sporifcr- 

 ous structure, loosely filling up the hood, is 

 composed of interlacing branched filaments, 

 bearing at their free ends globular cells 

 (asci or thecce) filled with spores. 



The Perisporiacei are likewise very simple, 

 consisting of parasitical Fungi growing upon 

 the leaves of trees or herbaceous plants. 

 They have a flocculent mycelium, often 

 radiating from a centre, where is found a | 

 membranous, sac-like, globular conceptacle, 

 containing sometimes a definite, sometimes 

 an iudetinite mmiber of clavate sacs or asci, 

 alone or mingled with paraphyses, and 

 containing ovate spores. The conceptacle 

 bursts either regularly or irregularh' at tlie 

 summit. 



The Sphseriacei have the conceptacles 

 more developed, either single, or associated 

 on a common receptacle, and consisting of 

 a firm capsular structure, hued with asci, and 

 opening at the apex by a regular pore in the 

 form of a papilla or beak when mature. 



The Phacidiacei difler chiefly in the de- 

 hiscence by slits, either single or longitu- 

 dinal, or several and parallel or stellate, or 

 circular so as to detach a lid ; most of these 

 have the sporanges collected on a common 

 receptacle, either of horny or fleshy consist- 

 ence. 



In these two families, and in Helvellacei, 

 Coniomycetous forms of spore are foimd 

 upon the same receptacle, either contem- 

 poraneously or at diflerent stages of deve- 

 lopment. Attention is directed to this sub- 

 ject under the head of that order ; and more 

 will be found under Sph^eia, Tympanis, 

 Ehytisma, Doth idea, Cobdiceps, &c. 



The true Tuberacei are Ascomycetous re- 

 presentatives of the Hypogseous Gasteromy- 

 cetes, being subterraneous, solid, globidar 

 or lobed bodies, of fleshy consistence, the 

 Truffle being a well-known example. The 

 organization of the Tuberacei is analogous 

 in all cases, but the structures differently ; 

 arranged. They all have an inconspicuous 

 flocculent mycelium, from which arises the 

 solid sporange. The sporange exhibits, when 

 cut across, an outer tough coat (peridium), 

 enclosing a fleshy structm-e excavated with 

 sinuous cavities giving it a marbled appear- 

 ance. These sinuous cavities are produced 

 by the convolutions of the fructifying 

 layer, which is folded and reflected back- 

 wards and forwards, leaving interstices 



which are lined with the asci or spore-saca 

 containing four or eight spores. The de- 

 gree of complexity of the lacunose mass 

 differs in dift'erent genera, being in some 

 simple, in others very complicated. 



The fructification of the Helvellacei vai'iea 

 much in form, the simpler resembling 

 closely some of the Phacidiacei : some kinds 

 are minute fleshy cups lined with asci form- 

 ing a superficial layer, as in Propolis ; or 

 they are large fleshy cups, often raised on a 

 stalk (Peziza), these cups being closed at 

 first, but opening widely afterwards. In 

 the Helvellce, the cup is converted into a 

 stalked mitre-shaped body clothed above 

 with asci. Others are of columnar form, 

 thickened at the summit, which is clothed 

 with the asci, as if a cup-shaped receptacle 

 had been turned down over it (Spathulea, 

 fig. .39 ) — tliis thickened head becoming more 

 considerable and excavated into little pits in 

 Morcliella. These plants are mostly found 

 on the ground or decaying vegetable sub- 

 stances, in damp places, and are frequently 

 of gelatinous consistence. 



If a Peziza, MorcheUa, Phyfisma aceri- 

 num, or similar Fungus, in its last stage of 

 development, is kept shut up in a bottle for 

 several hours, and then gently taken out, 

 the contact of the external air causes an im- 

 mediate and abundant explosion of spores, 

 which may be collected on slips of glass for 

 microscopic examination. If care is taken 

 in the experiment, it will be found that a 

 considerable quautity of a colourless hquid 

 is expelled with the spores, which liquid 

 contains minute molecules, and evaporates 

 very rapidly, leaving more or less apparent 

 spots on the glass. See Sph^ria. 



Synopsis of the Families. 



Helvellacei. Fruit fleshy, of various 

 forms, ultimately expanded, clavate, capi- 

 tate, stalked, mitre-shaped, cup-shaped or 

 beU-shaped, the upper surface clothed by 

 elongated sacs (asci), each containing eight 

 simple or septate spores. 



Tuberacei. Fruit (subterraneous) glo- 

 bular, with an adherent peridium ; solid 

 and fleshy within, and excavated sinuously 

 into numerous cavities clothed by asci con- 

 taining fom- or eight spores ; the internal 

 mass drying up or becoming pidverident or 

 floccose when mature. 



Phacidiacei. Fruit fleshy, simple or 

 branched, more or less cup-shaped in the 

 sporiferous region, which opens widely 

 or by a slit when mature, and exposes a 



