A COLUMELLA IN MARCHANTIA POLYMORPHA 
J.-B CRISES 
(WITH PLATES I, II) 
Introduction 
Marchantia polymorpha, because of its wide distribution and 
common occurrence, has long been used as a representative of the 
Marchantiaceae for laboratory study. The large number of sporo- 
phytes appearing upon a single receptacle gives excellent oppor- 
tunity to obtain various stages of development without much 
difficulty. Notwithstanding the wide usage of this species and the 
abundant literature dealing with the development and anatomy 
of the Marchantiaceae, it appears that in the organization of the 
capsule the tendency to develop a columella has never been 
recorded. 
In the work of Lerrces,’ Krenttz-Gertorr,? and others ob- 
servations are given on the development of the elaters within the 
capsule; and in each case these have been found to be irregularly 
disposed, appearing as elongated cells which are at first quite 
indistinguishable from the sporogenous cells, but soon may be 
detected by their failure to develop transverse walls. The present 
paper is concerned with some unusual incidents which may occur 
in the organization and development of these sterile tissues. 
The material from which these observations were made was 
collected during the first week of September 1914. It was taken 
from an exposed area which had been cleared during the previous 
fall and burned over. As is frequently the case in such instances, 
it developed here in dense formation during the following summer. 
My attention was first attracted to the appearance of columnar 
structures during the spring of 1915 while preparing material from 
this collection. Further study of a large quantity from this local- 
ity gave one additional instance of this type of organization. 
* Lettces, Husert, Untersuchungen iiber die Lebermoose. Vol. 6. 188r. 
* Krenrtz-Gertorr, F., Vergleichende Untersuchungen iiber die Entwickelungs- 
geschichte des Lebermoossporogons. Bot. Zeit. 32:161. 1874; 33:777-782. 1875. 
91] [Botanical Gazette, vol. 65 
