VINE : NOTES ON POLYZOA FROM THE CORNBRASH OF THRAPSTON. 257 
Locality and Habitat : on Echinoderm. 
5. Proboscina ornata, sp. n., pi. (XIII.), figs. 10, 10a, 10b. 
Zoarium flabellate. or very irregularly disposed ; some portions 
of the Zoarium apparently thickened by a secondary growth of cells. 
Zocecia contiguous, rather larger than the ordinary cells of the 
Proboscina species previously described ; cells thickly and minutely 
punctate, aperture circular. Ocecia very conspicuous and frequent, 
generally having a globular outline. In some portions of the Zoarium 
there are occasional cells, which differ considerably from the ordinary 
ones ; these are short or stunted, very broad across the central por- 
tion, but with apertures similar to the regular cells ; surface (smooth 
when worn), but normally the cells are finely punctate. 
Locality and Horizon : Cornbrash, Thrapstone ; generally on 
the shells of Echini. 
This beautiful species is not altogether rare, but examples show- 
ing the peculiar Ooecia are not abundant. The example selected for 
diagnosis have at least four, and associated with these are several of 
the modified oceciel cells referred to in the text. The colonial 
growths of the Zoaria are similar in some respects to the Zoaria of 
the next species which I shall describe, but the Zooecia are more 
depressed, and when superficially examined by a hand-glass some- 
what pellucid. On account of this peculiarity I referred to the 
forms in my original MS. notes as Probiscina pellucida, when 
returning the greater bulk of the fossils to Mr. Jesson, 
6. Proboscina Thrapstonensis, sp. n. PI. (XII.), figs. 6-6d. 
Zoarium flabelliform, fan-shape, lobulate or irregular, forming 
large and small patches, or colonial growths, and wholly adherent to 
a variety of fossils : Ostrea?, Terebratula species, and Echinoderms 
especially. Zooecia depressed, contiguous by their whole length, and 
nearly of equal breadth throughout : surface of the cells fiat, occa- 
sionally slightly rounded in the upper portions, especially in the newer 
cells, on the margins of the zoariums ; aperture circular, with a thin 
peristome placed at the extremity, depressed, or very slightly raised 
upwards just below the orifice. In the younger cells the surface is 
densely punctate ; in the older cells this feature is obscured by a thin 
coating of calcareous matter. — Ovicells ? 
