REPORT ON THE POLYZOA. 
71 
(1) Micropora uncifera , n. sp. (PL XV. fig. 7). 
Character. — Zoarium closely aclnate (on Eschara and Fucus). Zocecial area sub- 
rfiomboidal, broad (0 //, 02 to ’025). Border thin and sharp. Lamina concave, with a 
large oval opening on each side above. Surface very finely punctate. Orifice semi- 
circular, with a straight entire lower lip. Peristome thickened all round, but especially 
above, where it is strongly beaded. A small articulated marginal spine on each side of 
the summit. On the lower part of the front a very large and prominent avicularium, 
with an acute, incurved, uncinate mandible, pointing obliquely upwards — a correspondingly 
curved acute beak. Ooecia large, prominent, with a sinus or notch on each side at the 
bottom (not shown in the figure), and finely punctate. 
Habitat. — Station 135c, off Nightingale Island, 110 to 150 fathoms, and (135a), off 
Inaccessible Island, Tristan da Cunha, 75 to 90 fathoms, hard ground, shells, gravel. 
(2) Micropora coriaceci , Esper (sp.). 
Flustra coriacea, Esper. 
Discolor a coriacea, Lamk., Lamx., Blainv. 
Micropora coriacea, Gray, Smitt, Hincks. 
Membranipora coriacea, Brit. Mus. Cat. 
Character. — Front broadly elliptical ; margin terminating on each side of the orifice 
in a usually small (sometimes large) tubercle. Lamina punctate, occasionally with a per- 
foration on each side close below the orifice. Orifice semicircular, with a straight entire 
lower lip. Ooecia subimmersecl, with an umbonate projection in front. 
Habitat. — Station 135a, off Inaccessible Island, Tristan da Cunha, 75 to 90 fathoms, 
hard ground, shells, gravel (on shell). Station 75, lat. 38° 38' N., long. 28° 28' W., 450 
fathoms. 
[Shetland, Antrim, Cornwall, Guernsey, blastings, Caithness; Gulf of Florida, 
36 to 135 fathoms, Pourtales.] 
2. Vincularia, Defrance. 
Vincularia, Defrance; d’Oi'b. ; Stoliczka; Brit. Mus. Cat., &c. (all in part) nee Smitt; Cellaria, 
Eschara, Membranipora, Steganoporella, &c., &c., Auctt. 
Character. — Zoarium erect, continuous, branched or simple ; radicate or fixed. Sub- 
cylindrical or polygonal. Zooecia disposed in alternate longitudinal series. Frontal 
area quadrangular, oblong, arched above, in the natural state filled in by a chitinous 
epitheca, in which is seated the oral orifice. Beneath the epitheca a calcareous lamina, 
occupying the lower two-thirds of the area, and terminating above in a free border, 
from which a median process arises, wdiich, joining above a process from each side of the 
zocecium on a level with the lower border of the orifice, forms with those processes a 
transverse bridge with an arch on each side of the median process. Opercula incomplete 
