Sketch of the Class Fungi. 



7 



which bear the fruit. It is amongst the barren filaments that the 

 granules called conidia occur, analogous to the gonidia of Lichens, 

 and which must be cautiously distinguished from true sporidia*. 

 In proportion as the structure is more complex, these filaments, 

 erect or decumbent, which were at first free, or only more or less 

 loosely interwoven, are closely united, especially at the base, so as 

 to form a stem-shaped stroma, the extremity' of which, at a greater 

 or less distance, supports the sporidia. We see this disposition in 

 the genera Coremium and Isaria\, which M. Corda refers to Hyme- 

 nomycetes. 



In the second section, composed of Mucorin(£, the erect tubular 

 filaments, whether springing or not from a mycelium or decumbent 

 threads, swell at their free extremity into a vesicle. By observa- 

 tions which throw a brilliant light on the morphosis of these plants, 

 Corda (Ic. Fung. ii. p. 19. t. 11. f. 75.) has proved that the vesicle 

 or sporangium, at first in connexion with the cavity of the stem, is 

 soon separated by a columella or septum which is hemispherical, 

 campaniform, &c, of which he has been able to follow the develop- 

 ment, and upon which the spores, most frequently united like neck- 

 laces, acquire at length the degree of development necessary for the 

 reproduction of the species %. This vesicle, which is termed peridio- 

 lum, opens regularly or irregularly. 



In two genera (Pilobolus and Chordostylium) , analogous forms to 

 which we shall find in the Gasteromycetes, the peridium separates 

 entire from the summit of the simple filament which bears it, and is 

 thrown to a distance by an elastic force. Persoon and Corda, per- 

 haps with reason, place them in the following family. 



The fertile filaments of Hyphomycetes, extremely variable in their 

 form, are simple or branched, continuous or articulate, hyaline or 

 dusky, &c. Their mode of ramification varies with the species and 

 genera; it is dichotomous, verticillate, virgate, &c. Indehiscent, 

 and in themselves generally colourless and pellucid, they owe their 

 various hues to the juices which they contain. 



In Dematia, the fertile filaments, besides being usually destitute 

 of mycelium, or having one of a crustaceous nature, are remarkable 

 for their rigidity, and their olive, dingy or black hue ; they are sep- 

 tate, and bear sporidia adhering to the sides or tips of the threads 



* They often abound in the mycelia of Hymenomycetes, which are in 

 consequence described as Sporotricha. — M. J. B. 



t As regards the first at least, Corda's notion is quite untenable, for it 

 is more than doubtful whether its species be not mere modifications of Pe- 

 nicillia. Isaria most beautifully unites Hymenomycetes with Hyphomycetes 

 through Typhula. — M. J. B. 



+ On the strength of these observations, Corda has separated from true 

 Hyphomycetes this second section, in order to unite it to the following 

 family, changing its name into Myelomycetes. Ought we however to place 

 more reliance on the presence of a peridiolum than on the filamentous 

 structure and mode of vegetation ? The same might be said of Mcidium, 

 at present included in the foregoing family, and of which the same naturalist, 

 in consequence of the presence of a peridium, has likewise changed the 

 place in the system. 



