44 INTRODUCTION TO THE STUDY OF FUNGI 



The Maphomyceteae correspond to the Rymenogastreae in 

 being subterranean, similar in form, and alike enclosed within 

 an indehiscent peridium ; but they differ in the spores being 

 enclosed within asci, instead of being produced on basidia, and 

 in this respect are allied to the Pyrenomycetes. 



In so far as their final, and reproductive, stage is concerned, 

 the Myxomycetes resemble the Gastromycetes ; they are some- 

 times stipitate, possess a distinct peridium, in which the spores 

 are enclosed until maturity, and the latter are mostly coloured, 

 globose, sometimes rough, mixed with the threads of a 

 capillitium. On the other hand, the early or vegetative stage 

 is so different, that the ancient notion of their affinity must 

 be abandoned, although they are entitled to mention in this 

 place as Fungi which produce their fructification enclosed 

 within a peridium. Notwithstanding this, there are those who 

 regard it as heresy to mention the Myxomycetes on the same 

 page as the Gastromycetes. 



The fructification, which is produced within an open cup- 

 shaped excipulum, is of more than one kind, but the most 



important is that of 

 the Diicomycetes, in 

 which the spores are 

 ascomycetous — that is 

 to say, they are pro- 

 duced within asci. In 

 describing the recep- 

 tacles it was stated that 

 the fructiferous surface 

 was a compact stratum 



Fia.24.-SectionofhymemuminiW. Qr hymeniumj which 



overspread the interior of the expanded receptacle. In this 

 instance the fruit-bearing surface is superior, and soon fully 

 exposed to the light. It is plane or slightly convex when moist, 

 depressed and concave when dry, from the contraction of the 

 receptacle, and often brightly coloured (Fig. 24). The hymenium, 

 or disc, is composed of elongated cylindrical or clavate cells, 

 which are formed of a delicate hyaline membrane, splitting at 

 the apex, or opening with an operculum. These cylindrical 

 cells are closely packed side by side and constitute the asci, 



