Durand : Classification of the Fleshy Pezizixeae 489 



Helotiaceae as with the Mollisiaceae. The general habit of the 



plants, however, seems to associate them rather with the latter 

 group. 



Conclusions. — i. It is possible to separate the fleshy Pezizineae 

 into families of which the structure of the sterile layers of the cup 

 offers important distinguishing characters. 



2. Schroter's characterization of the Pezizaceae as having the 

 hypothecium and excipulum composed of rounded cells is too 

 general. Both cellular and hyphai tissues occur, but, as shown 

 above, the structure of the latter is peculiar to this family. 



3. Rehm's and Schroter's characterization of the Helotiaceae 

 as having the excipulum prosenchymatous is also too general. 

 This is the predominating tissue, but pseudo-parenchyma also 

 occurs. Both kinds are, however, uniformly thin-walled and light 

 colored. 



4. The Mollisiaceae have the outer excipular layer pseudo- 

 parenchymatous, the cells near the surface having thick dark brown 

 walls. 



5. Oil the basis of the preceding studies the families should be 

 characterized as follows : 



I. PEZIZACEAE 



Plants usually of medium or large size. Apothecia free on the 

 substratum, or rarely at first buried in the soil, fleshy, brittle, or 

 rarely leathery, sessile, or with a thick, fleshy stem, externally 

 smooth or pruinose, tomentose or pilose ; at first nearly or quite 

 closed, later more or less cupulate, concave or plane. Hypothe- 

 cium usually well developed, formed of rounded cells, or of stout, 

 septate hyphae. Excipulum pseudo-parenchymatous, or formed 

 of stout hyphae much bent and branched, septated and coalesced, 

 showing a transition to pseudo-parenchyma. Asci cylindrical or 

 clavate, not projecting above the hymenium, opening mostly by a 

 lid at the apex. Spores spherical to fusoid, commonly large and 

 one-celled. Paraphyses filiform, usually thickened at the apex. 



II. ASCOBOLACEAE 



Plants of small or minute size, usually growing on dung. Ap- 

 othecia free on the substratum, fleshy or rarely somewhat waxy 



