214 MADREPORARIA. 
the formation of an inner synapticular wall can be traced. The septa, like the wall ridges, 
are extremely thin and delicate ; fine septal granules rise above the synapticular wall, and thin 
plate-like pali in complete formula, the triplet being arranged like a trident with a flat central 
tubercle. The columellar tangle is very conspicuous. 
There is no section, and the colour is a greyish brown. 
The delicacy and thinness of the skeletal elements is one of the chief features of this 
coral, at least of all the upper parts of it. Round the lower edges the septa and walls become 
coarse and granular. The specimen is also remarkable from the fact that there are four young 
colonies on it of different sizes. They are all totally unlike the delicate calicles above 
described, but not unlike the thicker, coarser calicles of the lower edges, but this is enough to 
justify us in regarding them as colonies of this same coral. In the very youngest the calicles 
are incomplete and irregular, and bear no resemblance whatever to those of the adult colony. 
One cause of difference may be seen in the fact that the young colony rising very convex while 
its size is still very small, the calicles necessarily appear to be deep and conical. 
a. With four young stocks growing round the base. Zool. Dept. 86. 11. 22. 7. 
220. Porites Maldives (32. (P. Maldivium secunda.) (Pl. XXXI. fig.3; Pl. XXXIV. fig. 3.) 
[Maldives ; British Museum. | 
Description.—The corallum forms tufts of thin, narrow stems, the tips of which are 
flabellate and divide into short, blunt lobes or knobs 6-8 mm. thick, and under 1 cm. long; 
the stems may be either long and erect, or squat and fused together. The living layer extends 
only 4-5 cm. downwards, even at the outer edges of the stock.* 
The calicles are deep conical punctures, even down to the edges of the living colony. 
At the tips of the branchlets they are very deep, large (sometimes 2 mm.) and angular. The 
walls have sharp median ridges, porous, ragged, and membranous. These are mostly 
thickened into a reticulum, which near the creeping edge rises to the top of the wall ridges. 
The septa slope steeply inwards, and the wall thickening is apparently due to their synapticular 
thickenings, although there is seldom any regularity or symmetry visible. The fusions of the 
septa are quite irregular; they slope downwards and lose themselves in a granular tangle in 
the base of the calicle. There is thus no regular ring of pali nor central tubercle. 
The section of a stem shows a loose, open reticulum of stout threads with large meshes, 
and with obscured, irregular trabecule traceable round the periphery. The colour is a rich 
dark brown. 
There are two specimens of this coral. They resemble one another in having essentially 
the same kind of calicle and the same type of growth-form, only in the one (a) the flabellate 
branches are thin and erect, in the other (4) they are very short, freely fused, and with branchlets 
* Tn tuft formations it is usual to find that the living coral extends much further down the 
outermost stems than it does on any of the inner stems. 
