﻿. I TK/XSOX — COPRINUS 



pact even layer. In fig. 70, from a still older basidiocarp, it can be 

 very clearly seen that the surface hyphae of the pileus form a com- 

 pact palisade layer below the zone of large blematogen cells, 

 though the ends of the hyphae are not yet aligned into such an 

 even surface as they present later. Many of these hyphae repre- 

 sent new growth and branching of the earlier elements of the inner, 

 but not well defined, zone of radiating threads, and possibly some 

 of these older elements are incorporated in the palisade layer. 

 Whether any of them take part in the formation of the mature 

 palisade by abscission of the distal portion at the level of the pali- 

 sade surface, however, or whether all are compressed between the 

 broadening cells of the forming palisade and are thus merely 

 pinched off, as stated below, has not been determined. The 

 incorporation of some of the older hyphae into the palisade does 

 not seem improbable. 



The surface of the pileus is already beginning to show the 

 strong folds with' intervening depressions (" striations ") over cer- 

 tain of the older lamellae, which is clearly presented in the nearly, 

 or quite, mature plant. At the completion, or maturity, of the 

 palisade layer on the outer surface of the pileus, the cells are clavate, 

 very closely packed side by side, the free ends slightly convex 

 or nearly truncate (fig. 71). In this figure the broad folds with the 

 narrow intervening depressions are clearly brought out in cross- 

 section, the depressions, or "striations" as they are called, cor- 

 related in their position with the trama of the older, or primary, 

 gills, so characteristic a feature of many species of Coprinus. 



Shedding of the blematogen layer.— In the shedding of the 

 blematogen layer the greater part of the mass of rounded cells is 

 freed by the frail connection between the cells, perhaps due to a 

 weakening of the middle lamella accompanied by the rounding of 

 the cells and constriction between them. The chains of rounded 

 cells are formed on filaments of a few slender cells, some of which 

 project from between the cells of the palisade layer (a few can be 

 seen near the middle of fig. 69). As the palisade layer approaches 

 maturity, the crowding of the cells into the compact layer very 

 probably pinches off these slender supporting hyphae. A thorough 

 study of the shedding of the blematogen has not been made, but it 



