AUSTRALIAN PORITES. 139 
and often incomplete, with pointed angles. The septa have the same character as the walls, 
their edges being bent and slightly granulated. The pali are small, and not conspicuous, in 
formula Diagram B, fig. 3, p. 19, but with the palus on the ventral directive outside those 
of the two other members of the triplet (perhaps a septal granule, cf. formula H, fig. 3). The 
interseptal loculi are open and conspicuous; a central granular tubercle rises up in the fossa 
frequently as an axial strand of a columellar tangle. 
The texture of the vertical section is regularly and somewhat closely trabecular with 
sub-circular pores. The colour of the unbleached coral is ash-grey at the immediate surface, 
but the section shows a greenish layer about 1 mm. below it. 
The irregular columnar growth of this coral is interesting, especially so when compared 
with that of the next two, Nos. 36 and 37, the latter coming from the Gulf of Carpentaria. 
All these contrast greatly with all the other known Great Barrier Reef forms. 
a. Zool. Dept. 92. 12. 1. 536. 
129. Porites Great Barrier Reef (4936. (P. Queenslandie sexta et tricesima.) 
(Pl. XVIII. fig. 3; Pl. XXI. fig. 25.) 
[Great Barrier Reef, coll. W. Saville-Kent; British Museum. ] 
Description.—The corallum rises into a massive irregular ridge or crest, thickening as it 
rises, being 4—5 cm. thick when some 7 cm. high; the living layer is 5 em. deep. The top is 
broken up into deeply lobed longitudinal and transverse ridges. 
The calicles are small, under 1 mm., and only slightly pitted. The walls vary in thickness, 
either as single straight rows of finely frosted granules, or as thick low ridges with sloping 
sides, and as if composed of similar granules with minute pores or spaces between. The septa 
are thick where they run into the wall, and the narrow interseptal loculi are gashed back far 
into it. Their finely frosted thickenings are the septal granules, sometimes distinguishable as 
such. They are separated from the pali, which are large, similarly frosted granules. These 
two sets, together with the large oval central tubercle, over the greater part of the stock, 
seem to fill up the whole fossa, making the corallum dense. The pali, which hardly rise above 
the level of the septa, are in the complete formula B, fig. 3, p. 19; the principals and dorsal 
directives are large. The central turbercle rises to nearly the same height as the pali. 
The section is compact and trabecular, but the trabecule are not so close as the surface 
aspect of the coral would lead one to think. The colour of the unbleached coral is a pale 
fawn yellow. 
This is another Porites with an amorphous growth-form, similar to those of Nos. 35 
and 37, on which see the observations, Several worm-tubes run somewhat superficially through 
its substance, a factor which may have had some influence on its form. 
es Zool. Dept. 92. 12. 1. 529. 
T 2 
