274 STEIL: POLYPODIUM IRIOIDES 
visions have produced a small prothallium which has already 
formed a rhizoid. 
A number of antheridia were observed in which there was an 
unusual number of cells as is represented by Fic. 13. The lower 
portion (a) of this antheridium is peculiar since there was present 
an additional ring cell. 
ARCHEGONIA 
The frequent occurrence of secondary prothallia among the 
archegonia suggested that some of them may have originated from 
these sex-organs. By a careful examination of the prothallia, 
this idea was confirmed. Frequently pro- 
thallial filaments were produced from the 
neck and the venter cells, especially from the 
jatter. Fic. 14 represents a filament of a 
number of cells which has arisen from a sin- 
gle neck cell. -An early stage in the develop- 
ment*of a prothallium from a venter cell is 
a represented by TExT FIG. 2. The archegon- 
a young prothallium of ium which had opened in this instance bore 
Polypodium irioides pro- an egg (e) which had disintegrated. The 
ayn apteps oA filaments produced from the archegonia often 
grew to a considerable length and invariably 
developed numerous antheridia (TExT Fic. 3). Frequently 
FIG. 3. Regeneration from the venter of anarchegonium of Polypodium irio- 
ide. Numerous antheridia have been produced by the prothallial filaments. X 100 
plates of cells instead of prothallial filaments were developed 
from the archegonia (Fics. 15 and 17). 
