332 Mr. H. J. Carter on the Ultimate 
exception of Halichondria panicea, Johnston, is the commonest 
gical Supplement to his ‘ Sponges of the Adriatic Sea’ (Taf. 1. 
figs. 17 and 18 respectively, 1864), under the name of “ Wim- 
perkorb.” 
e smaller the specimen is, provided it be entire, the 
better, because it lives longer than the large portions, which 
more water and the water to be so often 
about 1-750th of an inch in diameter, and the sponge-cells of 
which they were composedabout 1-8000th of an inch in diameter. 
The ampullaceous sac was also seen in situ among the meshes 
of the spicular structure, and there also to be of the same size. 
n a subsequent occasion I found a pink portion of the 
same sponge, which appeared to have obtained its colour from 
growing in contact with a species of Rhodymenia ; and on 
tearing this to pieces I observed that the pink colour was con- 
ed to the ampullaceous sacs—that is, to the sponge-cells 
composing them. Hence I inferred that the sponge had been 
feeding on the fronds of the Rhodymenia, which sponges will 
do, just as fungi enclose and feed upon leaves and wood. 
As regards the colouring-matter of sponges generally, I 
think it will be found to be chiefly confined to the granular 
contents of the sponge-cells composing the ampullaceous sac. 
Thus, in Spongilla, when any part of this sponge presents 
a green colour, it appears to be confined to the granules of the 
sponge-cells of this sac,—that is, if the colour be in the sponge 
itself and not owing to the presence of a foreign agent. 
the scarlet sponges, to wit, Microciona atrosanguinea, Bower- 
nk (Se ina, Schdt.), it is confined to the ampullaceous 
sac and the still more scarlet gemmule which I have reason 
to think is but a transformation of this sac. Lastly, in a 
soot-black sponge (Dercitus (G.) niger, mihi) belonging to the 
f Notes on the Arrangement 
