208 CURREY, ON FRESH-WATER ALGA. 
four cilia. I find in the ‘ Regensburg Flora’ for 1855, a de- 
scription of the fruit of a Draparnaldia, published in Ra- 
benhorst’s collection, which is probably of the same nature 
as that which I have described above; the notice in the 
‘Flora’ is very short, and speaks of the specimen as being a 
curiosity on account of its fruit. 
There can, I think, be little doubt that these brown globu- 
lar cells are of a nature similar to that of the orange-coloured 
cells of Volvox, and the red cells of Bulbochete, Chlamydo- 
coccus, and other Algz; that is, that they are the resting 
cells, or, as they are sometimes called, winter spores, capable, 
as all such spores are, of undergoing desiccation for a 
lengthened period, and reviving again when circumstances 
become favorable to their development. 
I kept the bottle containing the Draparnaldia byme for some 
weeks, at the end of which time most of the brown cells had 
disappeared, and the water contained a mass of green Alge, 
which, at first sight, might have been supposed to belong to 
the genus Gleocapsa, but which appeared to me to have 
originated from the division of the contents, and from the 
softening and consequent enlargement of the outer mem- 
brane of the brown cells of the Draparnaldia. 
If these Gleocapse originated in the manner I suppose, 
the contents of the brown cells must have changed their 
colour during the process, but this, as is well known, is by 
no means an uncommon occurrence in the fresh-water Alge, 
when entering upon a new phase of vegetation. Not having 
had leisure at the time to follow out the process from day to 
day, I cannot state positively that the Gleocapsa-like Algze 
originated in the manner above mentioned, but it can hardly 
be doubted that such was the case, and the point is one which 
may afford matter for interesting mvestigation to any micro- 
scopist who may happen to meet with the Draparnaldia in the 
state of what may be called its winter fructification. 
The Gleocapsz, if I may so call them, which resulted from 
the division of the contents of these resting cells of Drapar- 
naldia, consisted each of a gelatinous envelope enclosing a 
number of small motionless green cells, or gonidia. In 
the oospores, or spores formed after copulation, of Spirogyra, 
I have seen the cell-contents divide into a number of 
round motionless cells, guite devoid of colour, and I have seen 
a similar process in one of the large orange-coloured spores of 
the so-called Volvoxw aureus, which is only the resting form 
of Volvox globator, where the contents divided into five 
globular colourless cells, which floated in a mass of reddish 
plasma, being apparently the remains of so much of the original 
