[Vor. 5 
214 ANNALS OF THE MISSOURI BOTANICAL GARDEN 
with the description of G. polyrhiza. Certainly, as Bornet 
and Thuret say, ‘‘Rien de plus variable que la configuration 
des sporanges." No two of the large number observed are 
of the same size or shape, and sporangia formed on the sur- 
face, a not infrequent occurrence, are just as irregular in out- 
line as those produced in the tissue of the wood. The con- 
tents of the sporangium breaks up into zoospores simul- 
taneously and not successively and the spores escape through 
a small hole invariably produced in the tip of one or more 
of the branch-like projections from the main body of the 
sporangium (pl. 14, figs. 2, 3). Bornet and Thuret were not 
able to observe zoospore discharge and thought possibly the 
entire sporangium broke up, thus liberating the spores. This 
is not the case in G. lignicola, however. A most satisfactory 
and simple means of obtaining discharging zoospore material 
is to transfer sporangia which have developed on unsub- 
merged parts of the wood. А part of the board which pro- 
jected above the surface of the water but, because of the 
cover on the jar, was constantly in a moist atmosphere, was 
filled with sporangia. If these were removed to a drop of 
water on a slide, zoospores would almost immediately begin 
to be discharged, one at a time, through the minute opening. 
In faet, the best sporangium material was obtained in this 
way, and it would appear that a habitat permitting at least 
semi-aérial conditions is best suited for sporangium forma- 
tion. So far as known, all the other species of Gomontia are 
to be found in situations which may permit either periodical 
or irregular intervals when the plant is not submerged, and 
it seems reasonable to suppose that such a habitat is conducive 
to the formation and discharge of zoospores. 
ZOOSPORES 
In the aecount of the original species of Gomontia, Bornet 
and Flahault deseribe the zoospores as having two cilia of 
equal length and of two sizes,—a small one measuring 53.5 
и and a larger опе 10-125-6 и. No conjugation, either be- 
tween small ones of the same size or between a large and 
