STEIL: POLYPODIUM IRIOIDES 275 
From the neck cells of these abnormal archegonia antheridia 
were also produced. Such antheridia were normal in development 
(Fics. 15 and 16). The antheridia thus produced also developed 
secondary ones (FIG. 16, 0). 
The archegonia at no time were found to de- 
velop secondary archegonia. The transformation 
of archegonia into prothallia was never observed. 
In these two respects the archegonia differed in be- 
havior from the antheridia. 
The archegonia with the behavior just de- 
scribed were like the antheridia, vegetative in yyg 4 Anar- 
nature, numerous chloroplasts being present in  chegonium of Po- 
the sterile cells. The axial row of cells of the /»Podium irioides 
archegonia from which regeneration occurred fre- | oe cells has 
quently disintegrated before the archegonia disintegrated. Di- 
opened. Such a stage is represented by TExT viding cells at a 
FIG. 4. It will be observed that some of the ah 
neck cells in this case have already divided (a, c). 
CULTURAL CONDITIONS 
It is impossible to state under what cultural conditions the 
sex-organs of Polypodium irioides regenerated in the manner 
described. Since no abnormalities appeared in the early history 
of the culture, it is probable that the peculiar behavior of the 
antheridia and the archegonia was the result of unfavorable con- 
ditions which appeared in the old culture. 
DIscuUSSION 
No case of regeneration from the sex-organs of a pteridophyte 
has been previously reported. In the mosses Correns* and C ollinst 
(1919) described the formation of protonemata from the antheridia 
of Funaria hygrometrica (L.) Schreb. Miss Brown{ found in 
the same species that protonemata could be induced to form also 
from the archegonia. In no instance, however, has the formation 
of antheridia been observed from either sex-organ of any bryophyte. 
* Correns, Carl. Untersuchungen iiber die Vermehrung der Laubmoose durch 
Brutorgane und Stecklinge. Jena. 1899. 
{ Collins, E. J. Sex segregation in the Bryophyta. Jour. Genetics 8: 139-146. 
IQIQ. 
t Brown, Mabel Mary. Unpublished paper. 
