g2 BOTANICAL GAZETTE [JANUARY 
Because of the dryness of the season and the infringement of more 
advanced stages of vegetation it was impossible to secure additional 
material from this locality during the fall of 1916. 
Investigation 
Two stages were observed in the organization of a central 
column of sterile tissue within the capsule. Fig. 1 gives a concep- 
tion of the extent of development in the simpler of these. It may 
be seen that the close assemblage of a large number of elaters in the 
center has resulted in almost complete sterilization there. It will 
be observed in this case, too, that the central column was not 
originally composed entirely of cells which developed elaters, but 
mixed with these were sporogenous cells which disorganized before 
they could form tetrads, leaving protoplasmic remains which take 
stains deeply. It is doubtful whether the disintegration of these 
is to be interpreted as a source of additional nutriment for those 
which remain, or is in any way to be associated with this behavior 
which is characteristic of members of the Jungermanniales. It 
seems rather to be an occurrence associated with the unusual, close 
development of sterile tissue, for it may be observed that imme- 
diately outside of this zone there is no such behavior. The cap- 
sule, in this instance, has developed to the point where the spores 
have become isolated from the tetrads, and the elaters are beginning 
to develop the spiral thickenings characteristic of their walls. 
These are laid down beneath the more or less spirally disposed 
protoplasm which is conspicuous at this stage. This columnar 
development is not the result of assembling the normal number of 
elaters into a central position, for the diffuse arrangement so char- 
acteristic of the species is still maintained in the rest of the capsule; 
nor is the number, excluding those in the central column, in any 
way reduced from the normal average. 
In the second stage of development (figs. 2, 3) there has been a 
complete elimination of sporogenous cells, so that the columella 
is composed of sterile tissue only. The sporophyte in this case was 
less mature than that represented in fig. 1. The scattered elaters 
show an almost evenly distributed protoplasmic content which has 
not yet collected preliminary to the formation of the spiral thicken- 
