VOLUME XLVI NUMBER 6 
BOTANICAL GAZETTE 
DECEMBER 10908 7 
BRYOLOGICAL PAPERS 
Il. THE ORIGIN OF THE CUPULE OF MARCHANTIA 
CONTRIBUTIONS FROM THE HULL BOTANICAL LABORATORY 120 
CHARLES R. BARNES AND W. J. G. LAND 
(WITH FOURTEEN FIGURES) 
The study of the cupule of Marchantia has evidently been con- 
fined to the later stages of its development, and especially to the 
origin of the gemmae and the order of cell division in them. Nowhere 
have we been able to find any account of the origin of the cupule, 
and the earlier stages of its development seem to have escaped obser- 
vation. Its homology with other structures in the upper part of the 
thallus has apparently been a matter of speculation rather than of 
Investigation. Thus, CAMPBELL casually remarks! that the gemma 
cup is apparently a specially developed air chamber, but gives no 
details and adduces no evidence therefor. 
Although Marchantia has been much investigated and indeed has 
been long a favorite subject for instruction in laboratories, KNY 
seems to have been the first to examine any of the early stages of 
development of the cupule itself. This he did for the purpose of 
illustratin g the development of Marchantia on his charts and describ- 
Ing the same in the accompanying text.” But he does not show or 
describe the origin of the cupule; the earliest stage referred to corre- 
sponds roughly to our fig. 10, when it has become a rather deep pit. 
Our studies upon the origin of the air chambers in Marchantiales? 
Suggested to us an inquiry into the origin of the cupule, to determine 
* CaMpBELL, D. H., Mosses and ferns, 2d ed. 44. 1995- 
2 Kny, L., Wandtafeln. Ser. III, pl. 84, text p- 366. 
3 BaRNES AND Lanp, The origin of air chambers. Bot. GAZETTE 44:197-213- 
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