CHAPTER XVII 



CArSULAR FUNGI PYEENOMYCETES 



Adverting to what has already been written of the Ascomycetcae, 

 it will be remembered that the largest and most important 

 group of those there enumerated is that of the Pyrcnomycetcs, 

 although, perhaps, the Discomycdcs may be considered as the 

 most highly developed. It may be premised that the total of 

 described species for the whole world, up to date, is not less 

 than 10,500, or not less than one thousand more than the 

 whole known Hymenoniycetes. The first distinct recognition of 

 the Pyrcnomycetes by Fries was in 1849, and then it was 

 supposed to include not only the SiJhaeriacei and the Peris- 

 poriacei, but also the Sphacrojjsidei and Melanconiaccae. In 

 more recent times, when ascigerous Fungi were separated from 

 stylosporous Fungi, the Pyrenomycetcs were revised, and the 

 ascigerous species only retained as a portion of the Ascomycetes. 

 With this limitation they are included in Saccardo's Sylloge 

 and universally accepted. Eeduced to its simplest designation, 

 the Pyrenomycetcs are ascigerous Fungi, having the fructification 

 enclosed within a perithecium, and growing on vegetable or 

 animal substances, but are never truly terrestrial. The various 

 families depend for their most prominent feature upon the 

 character of this perithecium. The form varies within definite 

 limits, as well as the texture and the mode of dehiscence. 

 Normally the form is spherical, or nearly so, and minute, 

 seldom much larger than a good-sized pin's head, and either 

 with or without a more or less elongated neck, not unlike a 

 miniature flask. This may be entirely immersed, or absolutely 

 superficial, or intermediate. The texture may be membran- 

 aceous or fleshy, and then brightly coloured ; or tough and 



