240 MADREPORARIA. 
The living layer extends downwards unevenly: surfaces raised into crowds of ceenenchymatous 
ridges 2 mm. high, blunt, rounded, bent and twisted in all directions. 
The calicles are minute, mainly visible owing to the rings of pali, which are 0°5-0°75 mm. 
in diameter, unevenly distributed, mostly confined to the valleys, but now and then sunk in 
the ridges. The walls and whole surface are covered with minute echinulate granules. The 
septa are obscured ; pali five to six, often slightly V-shaped, about the size of, and exactly 
similar to the rest of the surface granules. The columellar tubercle is hardly visible. 
The colour is reddish violet, especially in the higher parts ; below it is more yellowish. It 
occurs on the steep edge of the reef, frequently with Chama shells between the columns. 
This Porites from the Red Sea is interesting, as showing the upheavals of ecenenchyma 
common in Montipora but only rarely seen in Porites (see Table IV.). The differences between 
these ccenenchymatous Porites are seen not only in the methods of growth, but also in the 
forms of the ecenenchymatous ridging. The characters of the calicles show that all these are 
true Porites, and that nothing is gained by making them into a separate genus (see p. 9). 
251. Porites Red Sea 5. (P. Erythrew quinta.) (Pl. XXXIII. fig. 9.) 
[Koseir, coll. Klunzinger; Berlin Museum. | 
Syn. P. columnaris Klunzinger, Die Korallthiere des Rothen Meeres, ii. (1879) p. 41, pl. viii. fig. 22, 
pl. v. fig. 19. 
Deseription—The corallum is almost always columnar, but sometimes also in mounds or 
tubers. Columns often 50-100 em. high and 8-10 cm. across, generally narrowing towards 
the top like a blunt cone. The sides are irregularly swollen and humpy. The living layer 
extends nearly to the base of the column, at least 35 em., the lower edge tending continually 
to creep downwards over the dead stock. 
The calicles are moderately deep, very seldom flush with the surface, nearly uniform in 
size, rather large, 2 mm. across,0°5-1 mm.deep. The walls are thin, fenestrated, at the top 
of the stock generally sharp and polygonal. Sometimes the upper edge is not single, and then 
no longer projects as a sharp ridge, but combined with the septa is round-topped and reticular. 
Septa somewhat irregular, unequal, trabecular, and spiky (dornelig), The ring of four to five 
pali is conspicuous ; there is a distinct columella. 
In life the stock is of a brownish colour, but always deep black when dried. The black 
colouring matter reaches only 2 mm. below the surface. 
The above is taken from Dr. Klunzinger’s text and figures. Examination of the fragment 
obtained by the British Museum from Dr. Klunzinger shows also the following points :— 
By far the larger part of the axis of the columns is occupied by a rather dense streaming 
reticulum of stout threads or flakes; round the periphery the trabecule bend outwards radially. 
These trabeculze are rendered conspicuous by the fact that where the junctions occur they swell 
