POLYNESIAN PORITES 45 
Specimen a, from Kandavu (Pl. III. figs. 1, 2; Pl. XI. fig. 3). 
Syn. Porites arenosa (partim), Quelch (non Esper), Chall. Rep. xvi. p. 183. 
A large, heavy mass, with extensive lobulate surface. The calicles are small, little over 
1 mm. across. The septal granules, joined by short waists to the wall-ridge, are mostly large 
enough to unite, or nearly to unite, so as to form a ring of tissue, which turns the otherwise 
simple wall into a reticulum. The photographs show the differences between the calicles near 
the top and those near the lower edge of the stock. 
ss Zool. Dept. 86. 12. 9. 290. 
Specimen }, from Wakaya Reefs (Pl. III. fig. 3). 
Syn. Porites arenosa var. lutea (partim), Gardiner, Proc. Zool. Soc. (1898) p. 257. 
A very small stock, but already beginning to show the same type of lobulation as a. 
The calicles are, perhaps, a little larger. The septal granules are more flaky, and, while here 
making the walls reticular, there they form a shelf sloping from near the top of the wall-ridge 
down into the calicle. 
The name “ arenosa, 
name for specimen a. 
b. Zool. Dept. 1905. 1. 19. 1. 
7 
given by Mr. Gardiner, was obviously suggested by Mr. Quelch’s 
Specimen c is from the same locality. It is only a small chip. It shows a character of 
calicle seen only on part of 6. The skeletal elements tend to be very thin and flaky, with 
ragged or finely echinulate edges. The calicles lose much of the stiffness seen in a and parts of b. 
C Zool, Dept. 1905. 1. 19. 2. 
Specimen d, from the same locality (Pl. III. fig. 4), also part of Mr. Gardiner’s var. lutea. 
This shows the same type of lobulation asa and 8, but the calicles are much larger and 
shallower. The septal granules have expanded into large flakes, forming a broad level shelf 
or platform round the calicle, from the edge of which the septa project. The median ridge is 
conspicuous, though not high; it is now a thin connected string of frosted or finely echinulate 
granules. The large lateral pali are often V-shaped. The ring of pali appears a little more 
open than in a, and like those of b and c. 
d. Zool, Dept. 1904. 10. 17. 16. 
The fact that all these corals come from the same island group, have the same method of 
growth, or rather show the same peculiar form of surface lobule, and a strong similarity in 
septal and palic formul, while the differences in the aspect of the calicles can be attributed 
to the variations in development of one structural element—the septal granules—justifies 
Mr. Gardiner’s grouping, which we have here followed. Flakes sloping from the wall-ridge 
into the calicle occur again—e.g. P. Fiji Islands 18—where, however, it is not so easy to see 
their homology with septal granules, 
