REPORT ON THE POLYZOA. 
95 
tubes and fibres in this case differ from those of the deep water Bicellarice and other abyssal 
forms, in the circumstance that they have a tendency to coalesce and form flattened 
hands as above stated, in something the same way as in Kinetoskias. And it should also 
be remarked that in the present case the ultimate fibrils are not individually affixed to 
separate particles, but rather by their interlacement form a soft spongy or felted 
mass, the interstices of which are filled and, as it were, weighted by the foreign 
substances contained in the meshes, or even, as sometimes may be seen, received into 
actual pouches formed by the flattened membranous bands. 
The case affords a striking instance of the active organizing force inherent in the 
apparently amorphous chitinous substance of the radical tubes, which must be supposed, 
even down to the finest, to be lined by an active living tissue of some kind, — each segment 
in fact of every fibre being an actively living zooid as truly as are the zooecia them- 
selves. 
§ 2. compressor. 
2. Melicerita, Milne-Edwards. 
Melicerita, Milne-Edw., Ann. d. Sci. Nat., vol. vi. p. 26 ; 
d’Orb. Reuss, Stoliczka, Busk, &c. 
Melicertina , Ehrenb. 
Ulidium, Searles Wood. 
(?) Later eschar a, d’Orb. 
Cetlaria (sp.), Waters. 
Character. — Zoarium compressed, bilaminar, rigid, lobate, ligulate, or foliaceous ; 
articulated or continuous. Zooecia usually disposed in transverse rows. 1 Surface 
areolated. Area rhomboid or hexagonal. Orifice subcentral, semicircular, or oblong ; 
border entire, with two articular teeth below and sometimes also above. Operculum 
corresponding in form to the orifice, supported by a chitinous ring, incomplete above. 
In the conformation of the zooecia and general structure of the zoarium there is 
no essential difference between Melicerita and Salicornaria, the two, as I have remarked 
in the “ Crag Polyzoa ” (p. 70), very closely corresponding. The main distinction between 
the two forms consists solely, as it would seem, in the compressed habit of the one and 
the cylindrical form of the other. The transverse arrangement of the cells and the 
absence of segmentation, if this be real, are perhaps characters insufficient of themselves to 
entitle Melicerita to the place of a distinct genus in the Family Salicornariadse. 2 
1 The disposition of the cells in transverse series is the main character upon which the genus was founded by 
M. Milne-Edwards, but it is not one that can be regarded as of primary importance, since the same disposition occa- 
sionally obtains in several species of Salicornaria, and notably in Salicornaria malvinensis, in some part or other of the 
zoarium. 
2 In a valuable paper on the Fossil Chilostomatous Bryozoa from South-West Victoria, Australia, published in the 
Quarterly Journal of the Geological Society , vol. xxxviii. p. 322, 1881, Mr. A. W. Waters observed that Melicerita angustiloha, 
