Colour buff. Habit very peculiar. The polypidom rises to a height of seven or eight inches, with a long slender waving, but upright stem, which is naked inferiorly, and above gives off numerous straight or waving branches, again subdividing into other shorter straight ramules, about an inch long. The branches and branchlets are both pinnulated; the pinnules are not more than 1/10 to 1/12 inches long, extremely delicate and minute, so as in the dry state to be scarcely visible. The transition from the former section of the genus Plumularia to the present, is well shown, through P. macgillivrayi and the present species.
12. P. campanula, n. sp.
Cells campanulate, border entire; lateral and anterior appendages canalicular. Branches alternate. Ovicells ---- ?
Habitat: Bass Strait, 45 fathoms dead shells.
There appear to be two varieties of this species, or that different portions of the same polypidom may assume very different characters. The larger and probably more common form, is at first sight extremely like P. catharina, but it will soon be noticed that the branches are alternate instead of opposite. The shape of the cells and their average size is precisely the same as in that species. The lateral and anterior appendages differ in form very considerably. In P. catharina these organs are longer, more slender, infundibuliform, whilst in P. campanula they are shorter and thicker and the terminal cup is open on one side or canalicular. The ovicells might perhaps afford a more striking characteristic, but they are unfortunately wanting in all the specimens of P. campanula. The second variety is much slenderer, unbranched, the cells and their appendages smaller but of the same form, and the cells usually contain a mass of opaque black matter. This species is parasitic, and appears to attain a height of several inches.
Fam. 4. CAMPANULARIADAE.
4. CAMPANULARIA, Lamarck.
1. C. volubilis (?) Ellis.
Habitat: Prince of Wales Channel, Torres Strait.
As one or two ovicells, parasitic upon Sertularia pristis, are the only evidences of this species that have come under observation, some doubt as to identity of the species with the British form may be entertained.