Phylloblastia fortuita 5.jpg
Phylloblastia fortuita, section of perithecial wall. The wall is composed of two layers but these are interpreted as both being the excipulum (an involucrellum is absent). There is an outer layer of 1 to 2 rows of globular celled hyphae and an inner layer of compressed and elongate celled hyphae. (Specimen Powell 1949).