OF DENISON UNIVERSITY. 
13I 
on account of the unequal compression of the polyps. Their walls 
are not perforated, those of adjacent polyps are not intimately con- 
nected so that in case of fracture, the coral often splits along the 
middle of these walls Weathering will often loosen the polyps in a 
similar way. d'he broken coral then assumes a columnar appearance. 
The columns are longitudinally corrugated at regular intervals by 
continuous ridges, five or six on each side of its polygonal outline; 
and also transversely corrugated, but at very irregular intervals. 
There are also numerous transverse striae, which appear under a lens. 
Interiorly it consists of about thirty-five lamellae which extend from 
the walls towards the centre. The greater part disappear before 
reaching a distance within one milllimetre of the centre, and of the 
rest occasionally one or two reach the very centre; in that case some- 
of them sometimes seems to pass on for a slight distance beyond the 
center. The spaces between these lamellae are occupied by vesiculose 
leaflets or dissepiments. 
We do not believe that this species is really identical with the 
French species, but the structural similarity is greater with this species 
than with any other known to us. The Australian form however has 
a smaller number of lamellae, in a cross section they are seen to be 
often more or less wavy, and not uniformly straight as our figure 
would indicate, the number of disseppiments is also slightly less 
numerous than there represented. The general effect is however well 
given. These minute differences were noticed after the drawings 
were made. It differs from C. hexagonum, Goldfuss in the absence of 
a zone of thickening in the lamellae about the centre of the polyp. 
From C. rugosum, Edw. and Haine. it differs according to Rominger’s 
identifications, in the much smaller number of dissepiments, and in 
the fact that the lamellae do not lose their character at a certain dis- 
tance from the centre and then continue are mere ridges over the 
tabulae. The interior termination of the lamellae is far more regular. 
While our specimens show a close structural affinity with C. 
Boloniense^ the fact that we have not well preserved views of the 
calyces prevents our determining whether the slight variations 
observed are specific or varietal in nature. 
ENDOPHYLLUM . 
{Plate XIII, Figs. 16, 17.) 
Corallum composed of numerous polyps, polygonal or hexagonal 
