518 REPORT ON THE XENIIDAE COLLECTED BY DR WILLEY. 



Habitat. Isle du Phare Reef, Noumea, New Caledonia. 



This specimen certainly belongs to the species X. viridis, Schenk. Even the more 

 unimportant diagnostic characters of Schenk's species may be recognised in this specimen, 

 e.g. the strongly convex outer face of the tentacle, the thick soft stem, rich in coenenchym, 

 and the cup shape of the distal end of some of the polyps. 



Previously recorded from Ternate (Moluccas). 



NEW SPECIES. 



XENIA NOVAE BRITAXNIAE, sp. nov. 



There are eight specimens referable to this species, all of which are very similar in 

 shape, being dome-like or knob-shaped. The stem of the colony is usually single and 

 unbranched, but each of the two colonies from Lifu, marked ill. and D II. (see table 

 of measurements on p. .519), consists of two almost equal stems connected at their bases 

 by a thin flat band or membrane. The stem of the largest colony is 18 mm. high, 

 2.5 mm. x 15 mm. at the base and 30 mm. x 25 mm. at the summit. The .smallest colony 

 is about 5 mm. high and 8 mm. broad. 



The pol}'ps of all the specimens are small and resemble each other very closely in 

 the measurements of their various parts. The measurements of the fully-developed polyps 

 are: — body of the polyp 2-8 mm.- — 4o mm. long (a very few reach 5 mm. in length) and 

 •8 mm. — r3 mm. broad; tentacles 18 mm. — 3'5 mm. long and "7 mm — '8 nmi. (occasionally 

 1"0 mm.) broad. Each tentacle beai's three rows of short pinnules on each side of the 

 middle line. There are 8 — 12 pinnules in each row. The pinnules at the proximal 

 end of the tentacle are much shorter than the more distal ones. Seen from the 

 outer aspect the proximal three or four pinnules are small wart-like protuberances 

 ■17 mm. — "2 mm. long and '12 mm. — '18 mm. in diameter, while the moi-e distal ones 

 are longer and more typical pinnules "2 nmi. — So mm. in length and '15 mm. — "2 mm. 

 in diameter. They are largest in the middle of the tentacle and decrease slightly in 

 size towards its tip (see Plate LII. Fig. 2). Seen from the inner aspect the pinnules are 

 wart-like or club-shaped outgrowths standing almost at right angles to the face of the 

 tentacle (see Fig. 3). On the inner face of the proximal half of the tentacle there is 

 in the middle line a narrow area free from pinnules, but nearer the tip of the tentacle 

 the pinnules stand quite close together and many of them are flattened, on one or more 

 of their faces, by mutual pressure. 



In all the specimens buds occur apparently only on the edge of the summit of 

 the stem. These buds are similar throughout all the colonies. The smallest bud found 

 is "6 mm. long and its tentacles are simple rounded lobes '25 mm. long. A specimen 

 1-1 mm. long has simple but rather tiuger-shaped tentacles '4 mm. long. In a young 

 polyp 1^2 mm. long each of the tentacles is ••5 mm. in length and bears a small pinnule 

 on each side of the middle line. In a rather older polyp 1-7 mm. in length each of 

 the tentacles is '8 mm. long and bears two pinnules on each side. 



Spicules are abundant. They are generally oval discs measuring "2 mm. — 22 mm. 

 along their greater diameter, '015 mm. — -018 mm. along their smaller diameter and 



