﻿i 9 i6] ATKINSON-COPRINUS 95 



systems successive crops coming during rainy periods from spring 

 until late autumn. While the fruit bodies usually appear in dense 

 clusters, one can find clusters in different stages of development 

 at almost any time during this season. From young clusters the 

 basidiocarps of C. micaceus were collected. 



I have thus gone into the details in regard to the collection 

 of material for this study, in order to make it very clear that the 

 basidiocarps grown in the open, under normal conditions, on their 

 normal substratum, collected from young clusters, or scattered on 

 the mycelium (C. comatus), were undergoing normal development. 

 In these species it is fortunate that it is not necessary to grow them 

 in the laboratory, upon artificial agar media, in order to obtain the 

 young stages for study. 



Study of Coprinus comatus 



The general, annular, prelamellar cavity.— -It has not 

 been the object of this investigation to study the origin and differ- 

 entiation of the pileus and stem fundaments. The internal differen- 

 tiation of these fundaments has taken place before the fundaments 

 of the lamellae appear. The earliest stage yet studied in C. comatus 

 is represented in fig. 1 , from a section of the distal portion of a young 

 basidiocarp, the great bulk of the tubercle having been removed. 

 The young pileus is represented by the dark staining central zone, 

 bordered above and on the sides by a distinct zone of radiating 

 threads. The evidence appears to indicate that the system of 

 radiating threads has its origin at the stem end of the tubercle as 

 described by Brefeld (12) for C. lagopus, and that the fundament of 

 the pileus proper is differentiated soon afterward. The outer zone 

 of radiating threads is homologous with that which I have termed 

 the blematogen (Atkinson 8), and which Brefeld (12) calls the 

 pileus volva (" Hutvolva ") . But in C. comatus it remains "con- 

 crete" with the pileus, not separating from it as in the true or 

 finished volva (teleoblem) of the Amanitae. Within the funda- 

 mental elements of this system of radiating threads, toward its 

 center of origin, the pileus primordium becomes organized. The 

 lateral portions, that is, the margin of the primordium, which is nearer 

 the fundament of the hymenophore, appears to be differentiated 



