186 ARCHER, ON STEPHANOSPHERA PLUVIALIS. 
familiar Volvox globator.* In this organism some of the 
gonidia increase in size, become colourless; but, containing 
some brown or reddish particles, become detached from the 
circumference of the sphere, and acquire the power of pro- 
truding and retracting at various points the outer proto- 
plasmic layer (primordial utricle), just hke so many true 
Ameebe. By this power they glide along the inner surface 
of the sphere. Dr. Hicks enters into some arguments to 
prove that these are really the modified zoospores or gonidia 
of the Volvox, and not true Amcebz, which have entered the 
Volvox, and have devoured each a zoospore equal in size to 
itself, and then digested it. His arguments, indeed, that it 
is an actual change of the gonidium itself, seem irrefutable. 
But the ameeboid bodies of Volvox differ im some par- 
ticulars from those of Stephanosphera. In the latter they 
do not become colourless, as in the former, but retain, as has 
been stated, their green contents, but in a more disintegrated 
and loosely granular condition; they do not contain any 
reddish particles, as in the case of Volvox. In the case of 
Stephanospheera, as has been stated, the extremities of the 
amoeboid bodies are definitely distinguishable as an anterior 
and a posterior end, from the former only of which are the 
pseudopodal processes protruded, whilst in the amceboid 
bodies of Volvox there is apparently no such differentiation 
of the ends, and the processes are put forth in any direction. 
Dr. Hicks has not seen the amceboid bodies of Volvox to 
leave the old sphere and move about in a free condition. In 
the ameeboid bodies of Stephanospheera I have not seen any 
indications of a further change into the oval ciliated bodies 
described by Dr. Hicks. 
In his very interesting paper alluded to the same author 
cites two other cases of vegetable amoeboid bodies observed by 
him. He describes a change of the cell contents of the 
radicles of a moss into an ameeboid state: the contents of 
certain cells became detached from the cell-wall and collected 
into one or more ovoid masses, which sometimes became seg- 
mented ; their colour became temporarily changed to a reddish 
or reddish-brown, presently they lost colour, except a few 
reddish granules, as in Volvox, and became essentially amee- 
boid, travelling up and down the cells. Shortly they with- 
drew the pseudopodal processes, and became rounded and 
ciliated all over, beyond which Dr. Hicks’ interesting obser- 
vations were not extended. To these cases Dr. Hicks’ adds 
* ©Quart. Journ. of Microscopical Science,’ Vol. VIII, N. S.; ‘ Transac- 
tions of the Microscopical Society of London,’ p. 99, Pl. Vf (1860), and 
Vol. I, N.S., p. 96 (1862). 
