Habitat:  Port Curtis.  Off Cumberland Islands, in 27 fathoms fine grey mud.

Colour yellowish white.  Polypidom about 6 inches high, rising with a single flexuose stem, which is naked at bottom, and afterwards gives off alternate branches, bifariously disposed at each angular flexure.  Branches simple, 2 to 3 inches long; pinnules about 1/4 inch.  The construction of the ovarian receptacle in the present section of the genus Plumularia is well exemplified in this species, owing to the comparative simplicity of the elements of which it is composed.

2.  P. hians, n. sp.

Cell cup-shaped, deep, cylindrical; mouth nearly vertical; margin with three teeth on each side, the middle one the longest, acute, much expanded, the other more rounded; a wide notch posteriorly.  Rostrum, arising from the rachis, as long as the cell, slender, tubular, adnate; lateral processes very small, ovarian receptacles ——­ ?

Habitat:  Prince of Wales Channel, Torres Strait, in 9 fathoms.

Colour bright brown, rachis shining, very dark brown; polypidom about six inches high, simply pinnulate, pinnules about half an inch; thickly and regularly disposed, alternate.

3.  P. delicatula, n. sp.

Cell cup-shaped, rounded, mouth at an angle of 45 degrees; margin dentate, with two lateral teeth of equal size and a central one in front longer, all acute; entire posteriorly.  Rostrum a little longer than the cell, scarcely connected with the rachis, slender, and closely adpressed and adnate to the cell below, wide and projecting upwards; lateral processes large, rising above the margin of the cell, conical, tubular, or canalicular.

Habitat:  Prince of Wales Channel, Torres Strait, in 9 fathoms.

Colour of rachis and pinnules, delicate yellowish white above; of rachis, light brown, inferiorly; polypidom about two inches high, rising in several straight simply pinnulated fronds from a common centre; pinnules ascending about 1/4 inch.

4.  P. aurita, n. sp.

Cells cup-shaped, tapering at bottom, constricted just below the top; mouth at an angle of 45 degrees, circular; margin subcrenate, plicate, with three folds on each side, with a wide shallow notch in front and entire behind.  Rostrum, slender, attenuated below, adnate up to the cell, summit contracted, tubular; lateral processes very long, expanding, rising far above the margin of the cell, conical, tubular.

Habitat:  Off Cumberland Isles, 27 fathoms.

Colour bright brown; polypidom 2 to 3 inches high, consisting of straight pinnate fronds, pinnae or branches not opposite, nor regularly alternate, divaricate at rightangles.

5.  P. brevirostris, n. sp.

Cell sub-tubular, curved; mouth expanded with two equal acute teeth on each side, and a longer narrow and slightly incurved, central one in front.  Rostrum small, conical, projecting, about half the length of the cell; lateral processes small, recurved at an angle, canalicular.