58 
distinct from all previously known forms, but is in many 
respects so peculiar as to render it necessary to regard it as 
the representative of a still more general section of the class. 
The following characters will afford generic and specific 
diagnoses of the new Polyzoon. 
PHABDOPLEUPA, Allman. 
Ccenoecium consisting of a branched, adherent, membranous 
tube, in rvhose walls, along their adherent side, a rigid 
chitinous rod extends, and whose branches terminate each in 
a free open tube, through which the Polypides emerge. 
Lophophore hippocrepial, with a shield-like process on the 
haemal side of the tentacular series ; Polypides connected to 
the chitinous rod by a flexible cord or funiculus. 
Name. — ’Pa/3 Sog, rod, and vrXevpov, side, in allusion to 
the rod-like structure which is developed in the walls of the 
ccenoecium. 
Rhabdopleura Normani, Allman. PI. VIII. 
Ccenoecium sub-alternately branched ; ectocyst delicate, 
transparent, and colourless : free portion of the ccenoecial 
tubes of the same diameter as the adherent portion, and very 
distinctly and regularly annulated. 
Habitat. Creeping over the surface of dead shells from a 
depth of ninety fathoms. 
Locality. Shetland seas, J. Gwyn Jeffreys, Esq., and Rev. 
A. Merle Norman. 
The remarkable polyzoon for which the genus Phabdo- 
pleura has been constituted is eminently distinguished by the 
presence within its ccenoecium of a rigid chitinous rod (blasto- 
phore) (fig. 1 d, d, d). This rod runs along the adherent side 
of the ccenoecium, but is not found in the free prolongations of 
the branches through which the polypides move in the acts of 
exsertion and retraction. The rod contains an axile channel, 
which is very evident in the younger parts of the ccenoecium, 
where it may be seen to be filled with agranular pulp (fig. 9), 
but in the older parts the channel appears to have become 
nearly or even quite obliterated. 
At the points where the rod gives attachment to the funi- 
culus or cord, by which the polypides are connected to it, 
a slight enlargement of its diameter forms a sort of platform 
for the attachment of the cord, and at these points a very 
thin transverse septum would appear to be stretched across 
the tube, which thus becomes divided into a series of sepa- 
rate chambers, one appropriated to each polypide. The 
