Vol. 48 No. 9 
BULLETIN 
OF THE 
TORREY BOTANICAL CLUB 
The air chambers of Reboulia hemisphaerica 
(WITH TWENTY-TWO TEXT FIGURES) 
A. W. DUPLER 
INTRODUCTION 
The air chambers of the Marchantiales may be grouped under 
the three categories outlined by Leitgeb (12, 13, 14). These 
categories, named after characteristic genera, were defined by him 
essentially as follows: 1, the Riccia type, with simple air chambers, 
the chlorophyll being in the wall cells; 2, the Marchantia type, in 
which the simple chambers contain filaments of chlorophyllose 
cells; and 3, the Reboulia type, in which the primary chambers 
are more or less divided into secondary chambers by plates of cells 
arising from the sides, floor and even roof of the primary chambers. 
While the Reboulia type of chamber has been studied in other 
genera, Reboulia itself has received very little attention. . 
HISTORICAL 
In the literature dealing with the air chambers of the Marchan- 
tiales two general problems have arisen, so far as the Reboulia 
type is concerned. The first of these has to do with the question 
whether the subdivisions of the primary chambers are due to 
ingrowths into the primary chamber or arise as a result of schizo- 
- genous splitting of the thallus tissue. The second and more funda- 
mental problem has to do with the origin and early development 
[The BULLETIN for August (48: 219-240) was issued October 21, 1921.] 
241 
