AUSTRALIAN PORITES. 149 
small fragments from Franklin shoal. These are much thinner, and of a peach-yellow colour. 
These are the more remarkable, because if they belong here, and are regarded provisionally as a 
variety of a, they would form, with a, a couple of forms closely paralleled by a couple from 
the China Sea. So closely, indeed, do these two fragments resemble P. China Sea 10, that it 
is difficult to suppress the doubt whether some accident has not led to a confusion of the 
specimens. See the two forms P. China Sea 9 and 10, and the remarks upon them. 
a. Zool. Dept. 92. 4. 5. 40. 
d. Zool. Dept. 92. 4. 5. 39. 
¢, d, Zool. Dept. 92. 4. 5. 51 
142. Porites North Australia 5. (P. Australie Borealis quinta.) 
(Pl. XXII. fig. 6; Pl. XXIV. fig. 7.) 
[Blackwood Shoal,* Arafura Sea, 10 fathoms; British Museum. ] 
Description.—The corallum forms smooth stems, 3-3°5 em. thick at the base, and branching 
rather seldom and at small angles ; the branches taper gradually, and end in rounded points 
0°5 cm. thick. The living layer is at least 15 cm. deep, with encrusting edges. 
The calicles are large, 1°5-2 mm. in diameter, deep, and angular. The walls are simple, 
steep, and thin ; they are irregularly fenestrated, and have strong but ragged and uneven edges. 
The angles where they meet often rise into wave-like points, which, however, are not pro- 
nounced; buds sometimes appear in these angles. The septa project quite irregularly some 
way below the tops of the walls, mostly as triangular flakes ; these obscure the radial symmetry, 
the appearance of which depends so much upon the regularity of the interseptal loculi; the 
tips of the septa are thin, as small knobs or rods. The pali rise from these tips; they are 
very variable in number; the principals are always present, but not especially enlarged, and 
there are always one or two supplementaries. The central fossa is always deep, sometimes, 
indeed, without visible floor, at others a small tubercle can be seen rising from a compact 
reticular columellar tangle. 
The section of a stem shows the concentric elements of the skeleton especially strongly 
developed (compare the flaky septa). The trabecul, though stout, are so irregular as hardly 
to show as radial elements at all. 
The colour of the unbleached coral is a dark yellowish-brown. 
The specimen is unlike any other in the whole collection. Its growth-form is peculiar, 
the fine pointed branches are all curved one way, so that the specimen looks like a great bird’s 
claw. Its attachment seems to have been a weak one; the creeping layer of the colony seems 
almost as if closing over rotten coral, which represents the original stem. 
a, Zool, Dept. 92. 4. 5. 24 
* 9° 53'S, 129° 25’ BE 
