REPORT ON THE POLYZOA. 
109 
hexagonal areas, most of which present a rounded papillary eminence. Sometimes 
minute immersed avicularia within the meshes ; none on any other part of the surface. 
Habitat . — Station 172, Nukalofa, Tongatabu, 18 fathoms, coral mud. Samboangan, 
10 fathoms. 
[In the woodcut the anterior elongated mandible has been omitted. J 
(3) Retepora denti&ulata, n. sp. (PL XXVI. fig. 1). 
Character . — Zoarium expanded, flexuose, foliaceous, wavy, very irregular in form; com- 
posed of bifurcating, anastomosing branches, united very irregularly by transverse barren 
trabeculae. Reticulation very unequal, meshes more or less rhomboidal, much elongated 
and narrow. Zocecia rhomboidal or fusiform, flattened in front and deeply immersed. 
Orifice orbicular, notched in front, with a very minute avicularium on one side of the 
notch. Peristome, more especially in the lateral zocecia, much produced, subtubular, 
slightly infunclibuliform ; usually with two acuminate conical teeth on each side ; no 
spines. Ocecia inconspicuous. A few sparsely scattered large sessile 
avicularia placed on the front of the zocecia ; mandible spatulate, 
squarely truncate, pointing obliquely to one side ; beak bifid. Dorsal 
surface finely granular, indistinctly areolatecl, shining ; with deeply 
immersed avicularia, with blunt spatulate mandible, lodged within the 
lower angle of some of the fenestrse. 
Habitat . — Off Honoruru, Sandwich Islands, 20 to 40 fathoms. 
This species is distinguished from Retepora producta by the peristome 
in that species being much more produced, and its pectination limited 
usually to one side. In Retepora denticulata there are no marginal 
spines. 
The three preceding species, which constitute the whole of the reticulate or flamboyant 
group, appear to be closely allied, but yet in minute characters they are cpiite distinct. As 
will be seen, they all belong to the Pacific regions. 
Fig. 18 .—Retepora 
denticulata. 
§ /3. fenestratce. 
Zoaria foliaceous, fenestrate. 
§§ 1. Ocecia cucullate, closed, or more or less emarginate in front. Mouth orbicular, 
anterior border unarmed, simple or sinuate or subcanalieular (not fissured) ; no suboral 
pore. Operculum slightly produced below with a strong horse-shoe shaped rim. Dorsal 
avicularia numerous, usually placed within circumscribed areolae, or tessellae. 
