MALAYAN PORITES. 185 
There is no overlooking the resemblance of the fine texture of this coral to that of 
P. Singapore 1, yet it would be impossible to unite them. 
a-f. Parts of a stock. Zool. Dept. 98. 12. 1. 27. 
186. Porites Singapore (74. (P. Singaporensis quarta.) (Pl. XXVIII. fig. 4; 
Pl. XXXV. fig. 21.) 
[West Singapore, coll. H. N. Ridley ; British Museum. } 
Description.—The corallum consists of a clump of very thick stems, few in number, bent, 
twisted, and here and there fusing together into a compact mass. From their knobbed sides 
and ends, short, irregularly conical, round-topped processes project in all directions. The 
stems average 4 cm. in thickness ; their processes are from 1—1°5 cm. thick near their tips, 
and 2 cm. long. 
The calicles are conspicuous, circular, 1°5 mm. in diameter. The walls are thick, 
round-topped and reticular on explanate surfaces, with a lattice-work median ridge, which 
thickens regularly.* Higher up on the stock the walls are flaky, and the edge consists of a 
rather ragged filamentous reticulum, the early processes of the formation of new flakes. The 
septa are thick and symmetrical ; they show regular constrictions between the wall and the 
swellings which represent the septal granules, and again, between these and the pali. The 
latter form a large oval ring, in complete numbers and with a central tubercle, usually 
flattened in the directive plane. A columellar tangle can be seen just below the surface, 
frequently with a cruciform arrangement of bars joining the central tubercle to the lateral 
pali. 
The section shows a streaming axial strand apparently consisting of lamellate trabecule ; 
this comes to the surface in the round tips of the processes, and is surrounded by a thick layer 
of regularly radial trabecule, arranged compactly with rows of minute meshes separating 
them. The colour of the unbleached coral is a rich dark brown. 
This coral appears as if it started as an explanate stock, the central region of which rose 
up into a coarse bent conical process, which soon divided. There is such a young stock 
on specimen 0; it looks as if it were an independent colony which had started growing on a 
dead stem. ' 
The growth of the stems tends to break up the living layer into separate colonies. There 
are as many as four on the complete specimen made by fitting a and 6 together. The lower 
edges of these colonies frequently creep downwards, as if they were closely encrusting the 
dead lower parts. The specimen may have been free. 
The growth-form, the large size and the symmetry of the calicles, with their stout 
skeletal elements, ought to make it easy to recognise this coral again. On the small explanate 
colony above mentioned, it is noticeable that there is a tendency in the directive planes to 
run parallel with one another, 
a. Zool. Dept. 91. 8. 9. 14. 
b, Fits on to a. Zool. Dept. 91. 8. 9. 13. 
* By the addition of a synapticular ring. See Introduction, p. 16. 
2B 
