ABSTRACT
The fungi considered in this chapter are commonly called the ascomycetes and are the most diverse group of fungi. They are characterized by a specialized unicellular sporangium, the ascus (pl. asci), in which sexually derived spores, ascospores, are formed. The ascomycetes considered here are further characterized by the development of a protective structure, the ascoma (pl. ascomata), in which asci develop in a single layer or plane, the hymenium. The basic construction of the ascomycetes (and most other fungi) is filamentous and gives them tremendous surface area to absorb nutrients from their substrate.
