166 MADREPORARIA. 
irregular depressions or scratches in the flat surface of the reticulum, but they appear to be all 
slightly and irregular tilted, making the surface rough. The wall skeleton is melted down 
into a flaky reticulum, the surfaces and edges of the flakes being quite smooth and showing 
no surface granules. The flakes, tilted sideways and running into threads, build up an irregular 
layer without any apparent trabecular elements, at least at the surface. The calicles are 
distinguishable mainly by the round fossa circumscribed by a usually smooth complete ring 
from which a few irregular plates or flat rods stretch to the wall, seldom showing much regard for 
radial symmetry. The pali are represented only by a few slight thickenings on the rings 
surrounding the fossa. The interseptal loculi are very irregular and usually large, but only 
occasionally are they conspicuous, one here and there being deep like the fossa. 
This Porites is very remarkable in its texture; no others, not even the remarkable forms 
from the China Sea (No. 4) show such an extraordinary specialisation ot the horizontal elements 
of the skeleton (fig. 7). Attached to the specimen are layers of fine membranes built up by 
an encrusting Bryozoan; the resemblance between its flaky texture and that of the coral is 
noteworthy. 
Sheltered under the edges of the main stock is what appears to be a very young colony of 
a Porites which may be the same, but it is very different. It is also explanate and built up of 
a flaky reticulum, but the edges of the flakes are everywhere finely jagged. The walls are 
thinner, the septa are longer, and seem to meet irregularly in a central plate, which obliterates 
all traces of a fossa (fig. 8). 
What the inter-relationships of these two Porites are, whether this small one is a younger 
colony of the same or some quite different coral, cannot be decided. Nor do we know whether 
this attachment to a Gastropod shell is normal or merely accidental, nor, if the latter, how far 
the specimen owes its special features to this fact. 
a. Zool. Dept. 86. 12. 9. 314. 
6, a small stock under a. 
I conclude that the coral was carried about on the living Murew from the fact that it is 
tilted a little above the tip of the siphonal tube, as if to avoid the movements of the siphon. 
CHINA SEA (LO0-CHOO, MACCLESFIELD BANK, TIZARD BANK). 
164, Porites China Sea (ig1. (P. Sinensis prima.) 
[? Loo-Choo (Liu-Kiu) Islands, coll. Wm. Stimpson ; 2 | 
Syn. Porites tenuis Verrill, Proc. Essex Inst. v. (1866) p. 25. 
non Porites tenuis Quelch, Chall. Rep. xvi. (1886) p. 184. 
Description—The corallum is glomerate, globose, attached by a narrow stalk; surface 
irregular, uneven. 
