Durand: Classification of the Fleshy Pezizineae 471 



specimens in the Ellis and Everhart collection of North American 

 Fungi. Some forms were obtained from Rabenhorst's Fungi 

 Europaei, and from Roumeguere's Fungi Gallici. The remainder 



was found in the vicinity of Ithaca or was obtained from cor- 

 respondents in various parts of the country. Most of the ma- 

 terial was fresh or preserved in liquids. This was true of nearly 

 all of the Pezizaceae. The tissues of the Helotiaceae and Mol- 

 lisiaceae do not seem to be injured by drying. Such material, 

 after being soaked in water, was dehydrated and imbedded in 



collodion. This method of imbedding is well adapted to work of 

 this kind. 



The sections, varying from 6 ft to 20 fi in thickness, were taken 

 from near the base of the cup. The stipitate forms were cut 

 longitudinally through the middle of the stem and cup. 



Various stains were used, but alum eosin, acid fuchsin and 

 Delafield's haematoxylin gave the best results. 



Terms Employed. — The terms employed in this paper are those 

 proposed and defined by de Bary.* The term apothecium is ap- 

 plied to the whole sporocarp. It consists of two principal por- 

 tions. The fruiting layer or hymenium, and the sterile layers 

 beneath or partially surrounding the fertile part. The stratum 

 of hyphal tissue immediately beneath the hymenium is the hypo- 

 thecium. Grading off from the hypothecium is an often more 

 prominent and well-differentiated outer layer, the excipulum. 

 Frequently two layers may be distinguished in the latter portion. 

 The outer one, being usually more dense, forms a sort of mem- 

 branous ectal layer of the apothecium, and encloses a medullary 

 portion within. 



The term pseudo-parenchyma is applied to the parenchyma- 

 like tissue formed by the septation and coalescence of hyphae. 

 All gradations between true hyphae and the pseudo-parenchyma 

 may often be seen in a single plant. Prosenchyma is a tissue 

 composed of long, slender, interwoven hyphae. 



The several layers of the sterile portion of the apothecium are 

 usually not strongly differentiated, but often grade almost imper- 

 ceptibly into one another. It is upon the structure of the sterile 

 layers of the apothecium that the division into families has been 



I _ llu . j_ 1 ib - ~ 



De Bary (2), p. 187. 



