ASCOSPHOREAE 213 



C. Spore fruits much reduced, containing teliospores. 



Class Teliosporeae. 



D. Asci, basidia or teliospores unknown (artificial group). 



Fungi Imperfecti. 



Class 14. ASCOSPOREAE. The Ascus Fungi. 



333. This large class includes chlorophyll-less plants 

 which differ much in size and appearance, but which agree 

 in producing their fruit-spores (carpo- 



spores) in sacs (asci), and because they 

 are in sacs they are called sac-spores or 

 ascospores. These spore-bearing sacs 

 (singular, ascus; plural, asci) are end- 

 cells in the sporogenous tissue of the 

 fruit of the fungus, and they tend to Fio. 94.— Deveiop- 



. . r 'f ^ • mcnt of asci and 



develop m a layer of uniform height — ascospores. 

 the so-called ''h3^menium." 



334. The sexual organs where known consist of oogones 

 and antherids, and, after fertilization, produce a spore- 

 fruit (sporocarp) which includes the sacs and sac-spores 

 (ascospores). The most common number of ascospores 

 is eight in each ascus; but it sometimes exceeds, and fre- 

 quently falls short, of this number, there being sometimes 

 no more than one or two. 



335. In addition to the ascospores there are generally 

 one or more other kinds of spores which are developed 

 asexually. Some of these are doubtless to be regarded as 

 the equivalents of the conidia of the lower groups, and 

 accordingly will be so named here. 



336. The Ascus Fungi include about 29,000 species, 

 representing 15 orders and 80 families. In the treat- 

 ment hero a selection has been made of representative 

 forms. 



