34 BRITISH FOSSIL CORALS. 



Family EUPSAMMID^E (p. li). 



1. Genus Stephanophyllia (p. liii). 

 Stephanophyllia discoides. Tab. VI, figs. 3, 3 a, 3 b. 



Stephanophyllia discoides, Milne Edwards and J. Haime, Ann. des Sc. Nat., 3 mc serie, 



vol. x, p. 93, 1848. 



Corallum simple, extremely short, and discoidal ; its under surface almost horizontal, 

 somewhat prominent in the middle, and showing no trace of adhesion. Costa very narrow, 

 radiate, alternating with the septa, corresponding to these in number, and nearly equal in 

 breadth, but differing much in length, according to the cycla to which they belong ; the 

 smaller ones often united to the larger ones at their basis, and thus giving to the latter a 

 dichotomous appearance (fig. 33). All these costal strise are composed of a single row of 

 rather indistinct granule, and are united by small intercostal trabiculse, thus constituting 

 the tissue of the discoidal wall, and the radiate rows of pores that exist in this part of the 

 corallum, and give to it the appearance of a microscopical sieve. The upper or calicular 

 surface somewhat convex, and presenting in the centre a small, narrow fossula, at the 

 bottom of which there appears to be a rudimentary papillose columella. Septa forming five 

 cycla, of very unequal size, thin, very slightly granulated, not projecting laterally beyond the 

 edge of the wall, and having the upper edge rather angular. Those of the first and second 

 order large, straight, and free at their inner end ; all the others bent towards one another, 

 and cemented along their inner edge, so as to constitute a series of slightly undulated 

 arches, superposed and increasing in size from the circumference of the calice towards the 

 centre ; the largest are formed by the septa of the fourth cyclum, which unite two by two, 

 along the inner edge of the tertiary ones (which are very short), and thus constitute on 

 each side of the secondary septa a single lamina, that advances still further towards the 

 centre of the calice, and joins the neighbouring secondary septum opposite the point of 

 junction of its homologue, so as to give to the central portion of the calice the appearance 

 of a six-branched cross of Malta ; the septa of the fifth cyclum very small and marginal. 

 Diameter, two lines or two lines and a half ; height, about half a line. 



This fossil Coral differs from Stephanophyllia Suecica 1 and S.Bowerbankii (Tab. IX, fig. 4), 

 by the form of the septa, which in the latter two species are terminated by an arched edge, 

 and are spinulose laterally ; it is distinguished from Stephanophyllia astreata 2 by the distance 

 that separates the large septa near the columella, and from S. elegans? S. imperialist and 



1 See our Monograph of Eupsammidse, Ann. des Sc. Nat., 3 me serie, vol. x, p. 94. 



2 Fungia astreata, Goldfuss, Petref. Germ., vol. i, tab. xiv, fig. 1. 



3 Ann. des Sc. Nat., 3 me serie, vol. x, tab. i, figs. 10, 10 a. 



4 Michelin, Icon. Zoopb., tab. viii, fig. 1. 



