ARCHER, ON STEPHANOSPHERA PLUVIALIS. 187 
another, that of the amceboid transformation of the “ gonidia” 
of a moss, The “ primordial utricle” or outer protoplasmic 
layer became enlarged, at first feebly sending out short and 
rounded lobose processes. Afterwards the green contents 
vanished and the whole body became colourless, containing a 
few reddish-brown granules and some vacueles ; the processes 
became more elongate, and finally quite amceboid, moving 
freely about. 
To the foregoing may be doubtless added the case referred 
to by Hofmeister,* in giving an account of the structure of 
the ‘‘ spore-mother-cell ” of a particular moss, of which he 
writes—“ The cell contents, which are plainly surrounded 
by a thin layer of soft matter, very like a delicate membrane, 
swell slightly, or not at all; they (the cell contents) lie freely 
in the inner cavity of the cell, in the form of a closed 
vesicle, surrounded by watery fluid. Individual points of the 
primordial utricle sometimes exhibit slow expansions and 
retractions, similar to those of the inferior animals; for 
instance, the smaller Amceebe”” . . . . This is most 
probably a case in point, although the cell contents, still en- 
closed within the parent membrane, in the instance thus 
recorded, were not at liberty to remove. 
The only other published record of what truly seems an 
actual case in point, which I have met with, of a locomotive 
power due to an ameeboid motile contractility in an undoubted 
vegetable cell, is that by Schenk.t This author describes the 
nucleated, colourless, uniciliated zoospores of Rhizidium intes- 
tinum (a plant destitute of chlorophyll), as capable, during 
certain intervals, of moving about by the protrusion of ame- 
boid processes, each thus generally presenting a constantly 
changing two-, three-, four-, or five-lobed figure, the lobes pro- 
jecting in various directions, or for a time without lobes, and 
drawn out and very slender, whilst the internal movement of 
the granules was exactly that of an Amoeba. After some 
alternations of a still and a slowly contractile condition, and 
of an active movement by aid of the cilium with which each 
is provided, the zoospore finally assumes an elliptic figure, 
comes to rest, loses the cilium, and developes (more suo) into 
a new young Rhizidium plant. 
* Hofmeister, ‘On the Germination, Development, and Fructification of 
the Higher Cryptogamia’ (Ray Society’s Publication for 1862), pp. 1623. 
+ ‘Ueber das Vorkommen contractiler Zellen im Pflanzenreiche.’ Witrz- 
burg, 1858. 
+ Since this paper was read I have noticed a memoir by de Bary and 
Woronin, published in ‘Berichte ueber die Verhandlungen der naturfor- 
schenden Gesellschaft zu Freiburg, i, B’ (1864), entitled “ Beitrag zur 
Kenntniss der Chytridieen,” in which those writers (p. 30) state of the 
