174 Hitcucock: TOLYPELLA LONGICOMA IN CAYUGA LAKE 
noticeable growth of the plant where it was so abundant the 
year before. Perhaps the excessive early rainfall, which raised 
the water level and carried more sediment than usual, may 
account for this. 
The plant was first entered in my notes as T. comosa Allen, 
which was found in Seneca Lake in August, 1882. But T. 
comosa has considerably larger spores and differs in other minor 
respects. On further study there seems no doukt that the 
plant is most nearly related to 7. longicoma and that it can 
not be specifically separated therefrom. The Cayuga Lake plant 
is smaller and somewhat incrusted, the spores are black with 
seven or eight striae (not brown as described by Braun), and 
they ripen in July; otherwise there is no difference. 
The general habit of growth is shown in Fic. 1, which 
represents an entire young plant from the node above the 
protonema. Four conspicuous stem-branches have developed 
from the node, and these bear fruiting heads at the upper 
verticils. The close fruiting of the upper verticils of well-grown 
plants is shown in Fic. 5 and, somewhat enlarged, in Fic. 4. 
The sterile leaves which arise in verticils from the lower 
stem nodes are simple, very long, of uniform diameter through- 
out ay ‘slightly attenuate”” as Braun observed), about 0.2 
n diameter, and with blunt, rounded, and incurved ends. 
They are usually three-celled, with the terminal cell the longest, 
and may attain a length of 5 cm., thus exceeding the stem 
internode above. 
The fertile leaves divide near the base but have only one 
leaflet-forming and fruiting node, bearing an antheridium 
between two sporophydia and normally three short leaflets, 
two lateral and one dorsal, with a relatively long leaf terminal 
(Fics. 2, 3). The long terminals and leaflets are three-celled, 
not attenuate and are blunt-rounded. The first leaf-segment 
may be very short, 1-2 mm. or less, or considerably longer, and 
the terminal extension may be 2-3 cm. long or more. This is 
the typical form of fruiting leaves, but in the close-fruiting 
heads they are naturally quite small and, as Braun remarks, “the 
lateral leaflets either do not develop on the inner leaves of the 
smaller fertile heads, or, at least, are so dwarfed as to be in- 
distinguishable.” 
