POLYNESIAN PORITES. 87 
swollen ; except for that, the formula is that of G, fig. 3 (see Introduction, p. 19), the directives 
often running nearly across the calicle, involving the flattened central tubercle, and forming 
the trident with the vertical secondaries. Below the surface a conspicuous columellar tangle 
is visible. 
The calicles on some of the creeping edges low down are of a very different type. They 
are flush with the surface, which is a mosaic of erisp echinulate granules, in which the 
thick walls may be traced, and the calicles are recognised by the radial interseptal loculi 
and the concentric furrows between the wall- and the septal granules, and between these 
latter and the pali. (See Pl. VIII. fig. 6.) 
There is again only one specimen. Though it is of the same colour as the two pre- 
ceding forms, the differences in the structure of the calicles, as shown in the photographs, 
are so great that it is necessary to describe them separately. The calicles are not unlike 
those of P. Tonga Islands 6, but the resemblance is superficial. In this form pali stand up 
as a ring, visible to the naked eye from the shallow floor for the calicle. The convolutions of 
the surface are interesting. The specimen is not quite complete, but there is reason to believe 
that it forms, as stated above, a heavy knob upon the tips of the branches of other corals. 
a. Zool. Dept. 84. 12. 11. 13. 
65. Porites Solomon Islands 9 7. (P. Salomonis septima.) (PI. VIII. fig. 4; 
Vell, SCOUE, ster, 270) 
(Choiseul Bay, coll. Dr. Guppy ; British Museum. ] 
Deseription.—The corallum forms thick inverted pyramids, with smooth, nearly level top 
and rounded edges, and steep sides slanting inwards towards the base. The living layer is 
mainly confined to the upper surface, extending irregularly down the sides for from 1 to 3:em 
The calicles are small, 1 mm., deep and angular. Walls finely membranous, raised 
uniformly over the whole surface, only occasionally fenestrated, with ragged or denticulate 
edges, and with hardly any traces of septa appearing until some little way down below the 
fine edge. The first beginnings of the septa are small narrow-necked granules, putting out 
lateral synapticule for the formation of an inner wall-ring ; lower down they project far 
enough to form a fine palie ring round the fossa which joins the pali together, and is present 
in most calicles, though never quite complete. The pali, of which the four principals are often 
alone conspicuous, are tall, thin rods, The components of the ventral triplet often form a 
trident with a portion of the columellar ring. See formula G, fig. 3 (Introduction, p. 19). The 
columellar tubercle is small and granular, and attached to the ring supporting the pali by 
three to four spokes, one of which is at times in a line with the directive septa. A continuous 
directive line right across is seldom if ever seen. The interseptal loculi are deep, open and 
conspicuous, and either run into the fossa or are cut short by the formation of the columellar 
ring above described as joining the pali. 
