34 MADREPORARIA. 
TONGA ISLANDS. 
6. Porites Tonga Islands ag, (P. Tongaenis prima.) 
[Tongatabu, coll. Quoy and Gaimard ; Paris Museum.] 
Syn. Porites conglomerata (partim) Q. & G. (non Esper), Voyage de ‘1’Astrolabe,’ Zooph. iv. (1833) p. 249. 
Porites lutea, M.-E. & H., Ann. Sci. Nat. xvi. (1851) p. 28. 
Description.—The corallum tends to be short, columnar, with round, slightly swollen top, 
supported as a thick column or neck, covered with chalky epitheca. The living layer extends 
downwards about 2°5-3 cm. 
The calicles are very small, 0°75 mm. in diameter, hardly depressed, polygonal, or sub- 
circular, The wall is a thin, irregular, or zigzag thread, which is hardly visible to the naked 
eye. The septa project as frosted granules or points (not knobbed) from the margin, and are 
very irregular: two or three may sometimes be prominent even at the margin, but a short way 
below the surface they appear thick, obscure, frosted, and fusing together. There is a ring of 
pali sometimes complete (fig. 3, B). They are frosted, echinulate, and irregular in size. The 
fossa is conspicuous to the naked eye. The tubercle, usually flattened, is deep down, the 
interseptal loculi inconspicuous, but appearing as long thin slits in the lateral calicles. 
The specimen here described is in the Paris Museum, Z. 191a. It appears to be the 
original “variety” of the Porites conglomerata of Quoy and Gaimard, which Milne-Edwards 
and Haime re-named “ P. lutea.” The label bears the date “1829.” 
There are several stalked specimens from the Tonga Islands (see Nos. 4, 5, 6 in this 
Catalogue), but the calicles in no case seem to fit in with this description. 
The other specimens labelled “dutea” in the Paris Museum are quite different, as are also 
all the many “Jutea”s which are scattered through the records. This is another of those early 
names which has been given absolutely recklessly by nearly every writer who has “named” 
any Porites. 
For the type-specimen of the “P. conglomerata” of Quoy and Gaimard, the original of 
which seems to be lost, see P. Queen Charlotte Islands. 
7. Porites Tonga Islands qo2. (P. Tongaensis secunda.) (Pl. I. fig. 7; Pl. XIII. fig. 3.) 
[Tongatabu, coll. J. J. Lister; British Museum. ] 
Description.—The corallum is massive, the exact form being unknown; the upper surface 
is wavy, and rises to a blunt point. The living colony, which formed a small cap to a large 
dead mass, dies away progressively on all sides, without any edge formation. 
