Crisia boryi, Audouin. (Savigny Egypt plate 12 figure 4.)

Biserial; opening of cell oval or elliptical, rounded at each end, crossed in front, and thus divided into two nearly equal parts by a transverse calcareous band, from the lower edge of which depends a pedunculate, falciform operculum.  Cells frequently produced upwards into a large arcuate ovicell.  Vibracula ovoid, setae long, serrated.

Habitat:  off Cumberland Islands, 27 fathoms, fine grey mud.

Slender:  sufficiently distinguished by the peculiar form of the operculum.  This part is so indistinctly represented in Savigny’s figures, as to render it impossible to determine with certainty whether his species is the present one or not.  The posterior view is much more like, but that is insufficient of itself to afford a specific character.  The back of the branches exactly resembles an ear of barley.  This species occurs in New Zealand, and also in South Africa.

b.  Inoperculatae; opening of cell without an operculum.

3.  C. lata, n. sp. ?

C. dichotoma ?, Lamouroux.

Branches 4 to 7 serial; opening of cells in central rows, oval, sometimes square below; and the cell frequently produced into a shallow arcuate cavity.  A short blunt spine on each side of the mouth.  Marginal cells shallow, opening oval, margin much thickened, granulated:  usually a short conical spine at the summit; a very minute sessile avicularium behind the outer edge, superiorly.  Vibracula very large:  setae serrated.

Habitat:  off Cumberland Islands, 27 fathoms fine grey mud.

Colour white or yellowish; forms close rounded tufts 2 1/2 to 3 inches in height and width, composed of uniform dichotomously divided branches, about 1/8 of an inch wide, and which become wider towards their truncate extremities.  The vibracula are very large, and though distinctly defined, are yet sufficiently transparent to allow a view of the lozenge-shaped cells.  The central rows of cells vary in number from two to five, and the cells composing them are arranged with extreme regularity.  The marginal rows are placed in a plane posterior to the central, and as above noticed, the cells of which they are composed are widely different from the central.

The only other species with which the present can be confounded is Caberea hookeri (Cellularia hookeri, Fleming) a British form.  The latter species appears to differ from C. lata, chiefly in its having a large tubular spine on each side of the mouth of the lateral cells, and in each of the central cells, or nearly so, being furnished with an anterior avicularium, below the opening and to one side.  The lateral sessile avicularium on the marginal cells is also much larger.

Fam. 5.  FLUSTRADAE.

Polyzoarium expanded, continuous or encrusting.  Cells disposed in straight series, which do not radiate from a centre.

17.  Flustra, Linn.

a.  Cells on one side only.