Nov., 1922] LEVINE — LAMELLAE IN AGARICUS CAMPESTRIS 527 
center y as fully developed as x, and subsequent development brings about 
the opening of the palisade cells x and forming a young secondary gill 
which divides the old gill cavity into two. The young gill is fixed at z 
because of the continuity of the tramal elements between the pileus and 
stipe hyphae in this region. Further development of the gill cavities 
increases the width of the primary and secondary gills represented by / in 
diagrams 11 and 12. Growth takes place peripherally to s, at % and y. 
Very often these secondary gills break away from the fundamental 
tissue below them so that they remain somewhat narrower than the primary 
gills. It appears from these sections and from hundreds of similar ones 
that the secondary gills have a development identical with that of the 
primary gills except that their point of origin is at some distance from that 
of the primary gills. 
The cells of the stipe resemble those of other species of Coprinus in 
that they are multinucleated. The globular cells on the surface of this 
button shown in figure 83, Plate XXXIV, disappear at a later stage, as 
shown in figure 84. The cells making up the trama also disappear up to 
and through the pileus, so that the hymenial surface alone appears in older 
buttons. This condition gives the pilear surface its fluted or corrugated 
appearance. Figures 91, 92, and 93 represent cross, longitudinal tangential, 
and longitudinal median sections of the older carpophores of Coprinus 
stercorarius. The cells covering the pileus of this species apparently 
plasmolyze readily and give the appearance of globular cells with an irregular 
dark-staining body in their interior. These are intermingled with cylin- 
drical hyphal threads which also appear to be plasmolyzed. These cells 
give the scaly appearance of the mature pileus. I have observed carpo- 
phores with attenuated stems like those described by Brefeld. The pilei 
are much reduced and the stipes are very long, as shown in figure 88, Plate 
XXXV. The gills are merely narrow ridges as shown in figures 89 and 90, 
the latter of which represents a longitudinal tangential section. These 
forms are plainly abnormal. They may be found in material collected in 
the field among the belated specimens. 
I have also studied sections of Coprinus atramentarius made from 
material collected in the field. Buttons in all stages were found in a cluster 
that appeared close to a group of plants already mature. These young 
plants were fixed in diluted Flemming's weak solution, and the stages 
studied agree with those described for C. micaceus. No annular gill cavities 
were observed. Figures 94 and 95 represent median and tangential longi- 
tudinal sections respectively. The young gill Anlagen in both cases are 
attached to the fundamental tissue of the stipe region. It is clear from the 
data given above that, in the species of Coprinus so far described, the 
development of the carpophore and the formation of the gills are practically 
the same, with but slight variations as to the time of formation of the stipe 
or of the pileus. 
