DEVELOPMENT OF SOME SPECIES OF PHOLIOTA 
W. H. Sawyer, Jr. 
(WITH PLATES XVI-Xx) 
The taxonomy of the Agaricaceae at the present time is based 
upon characters of the mature plant which in many cases are slight 
and superficial and of uncertain homology. It is very probable 
that a knowledge of the origin and method of development of the. 
different structures composing the mature fruit body would aid 
greatly in determining true relationships among the different 
genera and Species, a ig is for this reason that a comparative study 
of th lop t of the basidiocarp is important. 
The first serious study in the Agaricaceae of the origin and dif- 
_ ferentiation of the parts of the young fruit body began over half a 
century ago, when HorrMann (19), in 1856, briefly described the 
origin of the hymenium in Agaricus campesiris and two other 
_ species. Four years later HorFMANN (20) gave a brief account of 
_ the development of several additional species, in all of which the 
hymenium was : Sangrpons in origin except one, Marasmius oreades. 
- In 1866 D ¥ (13) studied the development of several species 
of Agaricaceae, and his work was followed in 1874 by HartIc’s 
(18) description of Armillaria mellea, BREFELD’s (12) work upon 
Coprinus in 1877, and in 1889 by Fayon’s (15) very cursory study 
of 43 species, with hymenium both exogenous and endogenous in : 
_ origin. Nothing more was done along this line of research until _ 
: 1906, when ATKINSON (2) published a thorough description of the os 
t of Age np A 1 the stimulus given by th : 
- 4%. ne evide Se ee 1 ee 
s by se ry eee Ee 
a : tions on the development of “different agarics, a cee = oe 
_ ALLEN (1), BEER (11), and FISCHER a (16). ee 8 
= _Themateri forthe allowing investi 01 cc 
