NOTES ON A PECULIAR FORM OF POLYZOA. Ye 
may be seen to arise with a small transparent protrusion (a, 
a, a, a), which gradually increases in length and diameter, 
but in the latter sense very irregularly. Whether those 
tubes, which are attached at both ends, arise at one end and 
are inserted by the other, or whether the continuous tube is 
formed by the coalescence of a separate one from each side, I 
ain unable to determine, but am inclined, from the appear- 
ance the connecting tubes sometimes exhibit, to think that 
the latter supposition is the more probable. 
The continuous web-like connecting membrane appears 
in like manner to be formed by the lateral fusion of similar 
connecting tubes. But how the peduncle itself below the 
constriction at which it is attached to the sheathing mem- 
brane is formed is very difficult of explanation. It seems 
to me not improbable that the stem, notwithstanding its size 
and length, actually represents merely a segment or inter- 
node of a largely dilated radical tube, extending from the 
point of constriction above to the lower expanded end, where 
it breaks up into the bundle of fibres and fibrille, all of 
which, it may be observed, are more or less distinctly divided 
into joints or internodes, as is the case almost universally, 
so far as I am aware, in all radical tubes among the Polyzoa. 
In Kinetoskias cyathus I have not noticed any similar 
connecting tubes between contiguous branches, but the mode 
of formation of the web-like expansion is very plainly shown 
to arise from the coalescence of radical tubes. 
In fig. 4 is shown the bifurcation of a branch at a point a 
little above and including a portion of the edge of the web, 
whilst on the two outer sides of the figure are shown 
adherent portions of the same. It will be seen, as described 
by Professor Smitt, that a radical tube arising from the 
hinder and inferior part of a zocecium descends behind the 
outer border of the subjacent ones, and that the descending 
tubes on both sides becoming dilated, and gradually ap- 
proaching each other, eventually coalesce to form the mem- 
branous expansion by which the branches are connected. 
It is to be remarked, however, that at the angle formed by 
the edge of the web (8), the contents exhibit an aggrega- 
tion of minute germinal corpuscles, exactly like those which 
characterise the endosare in cell-budding zocecia. From 
this one might almost be tempted to suppose that the 
radical web possessed an innate power of growth or devel- 
opment like an ordinary zoecium, and that it is not alto- 
gether beyond the bounds of probability that it may, in 
some cases, throw tubular prolongations wpwards along the 
sides of the zowcia above. This surmise is strengthened by 
