On the Polyzoa of Queen Charlotte Islands. | 49 
V.—Report on the Polyzoa of the Queen Charlotte Islands. 
By the Rev. Tuomas Hincxs, B.A., F.R.S. 
[Continued from vol. xi. p. 451.] 
[Plates III. & IV.] 
~ LEPRALIA (part.), Johnston. 
Lepralia bilabiata, n. sp. (Pl. ILL. fig. 1.) 
Zoecia quincuncially arranged, short, very slightly convex, 
the sutures little more than incised lines, rounded above 
(where the cell-wall forms a distinct border round the orifice), 
widening out at each side, and narrowing off towards the 
base, which is subtruncate or pointed; surface dense, smooth, 
of a somewhat waxy appearance and a dark brown colour; 
orifice large, occupying nearly half of the front surface, rounded 
above, slightly contracted a short distance above the lower 
margin, which is arched outwards; peristome unarmed, not 
elevated; operculum smooth, of a deep black colour, with a 
slight rim round the edge, the inner surface attached to a bi- 
labiate tubular passage (Pl. IIL. fig. 1), through which the 
polypide issues. Avicularia none. Ocwcium a subtriangular 
extension of -the cell above the orifice, very little raised, a 
great part of its front surface occupied by a large foramen, 
closed in by membrano-chitinous material (Pl. ILI. fig. 1 a). 
Zoarium of a very dark brown colour (almost black). 
Houston-Stewart Channel, on shells. 
When the zocecium is open, the orifice is occupied in great 
part by the entrance to a tubular passage, through which the 
polypide issues; this entrance is bilabiate, the lower lip con- 
sisting of a semicircular chitinous rim, as it were soldered 
to the inner surface of the operculum ; the upper or opposed 
lip, also chitinous, is movable, and closes upon the opercular 
lip when the polypide retreats. 
The structure of the ovicell in this species is peculiar; it 
consists of a short extension of the cell upwards, the front 
wall of which is much depressed, and bears a large foramen, 
with a chitinous lid or covering. The ocecial chamber is 
small, and the entrance to it is closed by the operculum of 
the cell. This is a very distinct modification of the ordinary 
form of ocecium. i 
L. bilabiata is luxuriant in growth, and forms very large 
spreading crusts. 
Ann. & Mag. N. Hist. Ser. 5, Vol, xiii. 4 
