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tact with the wet soil develop rhizoids, ventral scales, and open air chambers, 
while those whose apical ends do not touch the soil dry and soon die, giving 
some shade to the delicate plants below. My observations have not been 
conducted over a sufficient period of time to determine fully whether these 
plants produce sex organs and fruit as some observers would have us think , 
actually occurred. In the Deming ponds east of the city limits of Terre 
Haute aquatic R. fluitans grows abundantly. During the summer and 
autumn of 1913 these loess encircled ponds became dry due to the long 
continued drought; however, many thalli remained alive in wet shaded 
places throughout the dry season. These plants remained in contact with 
the earth sufficiently long to fruit, judging from experiments made upon other 
Riecia, however, no sporophytes were found. When weather conditions 
were more favorable for hepatic growth searches were made for rosettes and 
thalli typical of terrestrial R. fluitans but none were found, indicating that 
spores had not been produced or had not had time to germinate. Weather 
conditions of 1914 were similar to those of the fall of 1913. At intervals 
during the autumn frequent observations were made but yielded no satis- 
factory evidence. Again in 1915 careful searching was done, without gaining 
additional results. Similar observations were made at Rosedale in the 
‘“Niggar Lake” region, no rosettes or thalli on the mud were found. Judging 
from these observations it seeimus very doubtful if the aquatic form ever 
changes into the terrestrial form or fruits but reproduces vegetatively only. 
It is very doubtful if the so-called terrestrial R. fluitans and the aquatic 
R. fluitans belong to the same species. 
The terrestrial R. fluitans is not common in this region; however, it occurs 
in small patches on mud flats and wet fields during the autumn. It generally 
grows in rosettes due to the fact that the spores are not scattered but held 
within the archeground pit, and that the sporophyte is generally buried in 
the mud. The thalli are about one-quarter inch long and less than an eighth 
of an inch wide. The plants have a characteristic green which is tinged 
with purple late in the autumn. Numerous rhizoids develop from the ventral 
side. A single row of scale leaves which split into two rows grow just beneath 
the apical cell. The most prominent ventral mark of identification is the 
protruding sporophyte. The dorsal surface is cut by a furrow which deepens 
at the apical end into which the pores of the alternating sex organs open, and 
down which the sperms are carried by moisture. Above the fertilized egg 
develops a tongue-like projection which covers the mouth of the arche- 
~” 
os 
