IN VEGETABLE BIOLOGY. 371 
drawn immediately upon my getting a sight of what was 
going forward. The two zoospores denoted by c were moving 
together and quite apart from the rest; the four denoted by a 
were also moving together, but their motion was but feeble, 
and still feebler was that of the two marked 5; the middle one 
was motionless. Immediately north of these zoospores was a 
brown discoloration, betraying the former presence of an Apio- 
cystis zoosporangium ; and I am inclined to believe that this was 
the last stage in its zoospore-liberation ; but inasmuch as in all 
cases in which I have studied the escape of the zoospores from 
start to finish, no evidence of such a coenobial phase has come to 
hand, the identity of these zoospores with those of Apiocystis, 
large examples of which they much resembled, must remain 
doubtful. No trace of an investing wall was observed here, and 
the connecting substance could not be distinguished from the 
water. After moving about for a little while, these zoospores 
became isolated. 
Other Phases in the Life-history. 
It will be observed that many of the gonidia, even when their 
fellows are provided with cilia, are figured as devoid of those 
appendages. In some cases (e. g. figs. 9, 14, 29) cilia were dis- 
covered only with great difficulty. I am not, however, disposed 
to think that the gonidia are in these cases eciliate throughout 
life. Probably identity in refractive index between the gelati- 
nous matter and the water may to some extent account for this, 
the former swelling up round the cilia; and besides this, gela- 
tinization of the wall may be accompanied by disappearance of 
the cilia. This opens up the question whether the forms drawn 
and described by Naegeli as eciliate were so in reality. His re- 
striction of cilia to autumnal states is an obvious mistake, many 
of my figures having been drawn during the spring and summer, 
and individuals with long cilia being still in existence this present 
month (December). One is therefore justified in suspecting, not 
that his earlier observed forms were eciliate, but that his atten- 
tion was not directed to the cilia until later in the year. And if 
this should be thought impossible in the case of so well-tried an 
observer as Naegeli (working, however, with the instruments of 
forty years ago), I may mention that it has often happened to me 
to come upona presumably eciliate specimen in which the fact of 
LINN, JOURN.— BOTANY, VOL. XXV. 2D 
