228 BRITISH FOSSIL CORALS. le 
ASTREA HELIANTHOIDES, Lonsdale, Geol. Trans., 2d. ser., vol. v, p. 697, 1840. 
DiscopHYLLUM HELIANTHOIDES, D’ Orbigny, Prod. de Paléont., vol. i, p. 106, 1850. 
CYATHOPHYLLUM HELIANTHOIDES, Milne Edwards and Jules Haime, Pol. Foss. des Terr. 
Paleeoz., p. 375, pl. viii, fig, 5, 1851. 
STREPHODES HELIANTHOIDES, M*‘Coy, Brit. Paleeoz. Foss., p. 73, 1851. 
Corallum simple or composite. 
When simple this species is subturbinate, short, broad, with the edge of the calice 
reverted, so as to form an obtuse prominent ridge around the central fossula. Sixty or 
eighty equally-developed septa, slightly thickened towards the exterior by the granulations 
and strize that arise from their lateral surfaces; almost all of these extend to the centre of 
the calice, where they become slightly curved, and present, in the well-preserved 
specimens, small but well-characterised paliform lobes, which, by their agglomeration, 
form a sort of crown near the centre of the calicular fossula. The edge of the calice is 
circular and slightly lamellate. The height of the corallum is usually about two inches, 
and in that case the diameter of the calice is about double, or somewhat more, and 
that of the paliform circles about four lines. 
When composite this corallum assumes an astreiform appearance, and the corallites, 
which are united together side by side, are circumscribed by polygonal lines, usually not very 
prominent. The ca/ices are in general smaller than in the simple specimens, very unequal 
in size, and not provided with as many septa. In a variety of this species, the calicular 
swelling is large and prominent. Vertical sections show that the central part of the 
visceral chambers is occupied by slightly-developed tabulz, and the outer parts filled with 
numerous and somewhat regular vesicles. 
Found at Plymouth, Teignmouth Beach, and Mudstone Beach; in France at Viré 
(Sarthe) ; in Germany, in the Eifel, Rokeskill, Blankenheim, Steinfeld, Luxembourg, 
Reinfeld, Sigmaringen ; in America, at Harrisville, Ohio, and in the Isle of Mackinaw. 
British specimens are in the collections of Mr. J. S. Bowerbank, Dr. Battersby, 
and Mr. Pengelly. 
The species of cyathophyllum that most approximates C. helianthoides is C. Regium,' 
from the mountain limestone; but in the latter the simple corallites are more regularly 
turbinate, and the calice is not everted so as to assume the form of a mushroom; the 
septa are also more numerous and slender. 
9. CYATHOPHYLLUM HEXAGONUM. ‘Tab. L, figs. 4, 4a. 
Maprepora TRUNCATA? Esper, (Pflanz.) Petref., tab. iv; (not Linne). 
CYATHOPHYLLUM HEXAGONUM, Goldfuss, Petref. Germ., vel. i, p. 61, tab. xx, fig. 1, 1826. 
FavasTREA HEXAGONA, De Blainville, Dict. Sc. Nat., vol. Ix, p. 340, 1830.—Man., p. 375. 
ASTREA HEXAGONA, Steininger, Mem. Soc. Geol. de France, vol. i, p. 345, 1831. 
' Tab. xxxii, figs. 1—4. 
