Habitat: Prince of Wales Channel, Torres Strait, 9 fathoms.
Colour pale buff. Polypidom five or six inches high, consisting of a strong straight, tapering stem, sometimes with a single ascending branch given off near the bottom; stem and branches pinnate; pinnae 1 1/4 to 1 1/2 inches long; alternate, and arranged with the utmost regularity, of uniform length, till near the summit, when they shorten rapidly, so as to give the polypidom a rounded truncate end. The pinnules are excessively fine and delicate, not more than 1/10 to 1/12 inch long, and very closely set, so that the whole polypidom has the most exact resemblance to a beautiful silky quill feather.
10. P. macgillivrayi, n. sp.
Cells campanulate, deep, rounded at bottom; margin subplicate, entire. Rostrum large, rising from the cell, adnate the whole length of, and as long as, the cell; the upper third constitutes a cup distinct from the lower portion; lateral processes adnate, wide, short, curved upwards, canalicular or tubular. Costae of ovarian receptacle connected by a membranous expansion.
Habitat: Louisiade Archipelago, reefs at low water.
Colour bright brownish buff. Polypidom six to seven inches high, consisting of a strong central stem, giving off opposite branches, at regular intervals, and bifariously disposed. Pinnules about 1/8 inch long, closely set.
b. Gymnocarpeae--ovicells naked.
11. P. effusa, n. sp.
Cells urceolate; deeply emarginate posteriorly, entire in front, ventricose below; a small pedunculate infundibuliform process attached in front to the projecting portion of the rachis on a level with upper border of the cell. Ovicell ---- ?
Habitat: Prince of Wales Channel, Torres Strait.