1895.) Aquatic Fungt. 481 
Gonapodya polymorpha, n.sp. Plate XX XJ, figs. 11-16.— 
Hyphe irregularly branched, more or less regularly divided 
into short oval or irregular segments, the segmented portion 
arising directly from the substratum or more often confined to 
tufts of branchlets borne sub-umbellately on the ends of slen- 
der elongate hyphz in which the segmentation is indistinct or 
obsolete; the segmentation frequently ill-defined or obsolete 
throughout the whole vegetative body. Sporangia variable 
in size and form, long-oval, tapering rather abruptly to the 
blunt tip, terminal and solitary or sometimes several arising 
from a single segment, ‘once to several times proliferous, the 
hypha sometimes traversing and growing beyond the empty 
sporangium. Zoospores very variable in size and number. 
Hyphz 200-1000 long. Sporangia 20-60 x 12—30#. 
On submerged twigs and other vegetable matter. Vicinity 
of Cambridge, Mass., and Kittery Point, Maine. 
his species seems very common and may be obtained from 
almost any body of still water. Its variability is extraordin- 
ary and did not intermediate forms constantly occur one 
would not hesitate to separate specifically, if not generically, 
forms in which the segmentation of the hyphe is most prom- 
inent and those in which it is nearly obsolete. Careful search, 
however, shows the presence of pseudo-septa unassociated 
with constrictions even in the unsegmented forms. When the 
segmentation is pronounced it is often even more clearly de- 
fined than in G. sé/iguaeformis, as in fig. 15, and in such in- 
stances the segmented portions are more often confined to 
tufts of branchlets borne on slender hyphe as in figs. 11 
and 12. 
The oospores represented in fig. 16 have several times been 
found unassociated with any other zoosporic form, but, as has 
been already mentioned, a definite connection between the 
two has not been traced. They occur near the base of the 
ordinary filaments embedded in the mass of bacteria and for- 
eign matter which is usually associated with this plant. 
These oospores, which recall those of Rhipidium in several 
respects, are about 54 in diameter, the laminated refractive 
walls 18 thick, with the rounded antheridium usually per- 
sistent. 
_ The extremes of size exhibited by the zoospores are shown 
in fig. 14 in two sporangia which were borne side by side on 
the same filament. The general appearance of the zoospores 
