294 BRITISH FOSSIL CORALS. 



epitheca, and presenting very irregular accretion wrinkles. Upper surface slightly convex, 

 and presenting large polygonal prominent reticulations formed by the line of junction of 

 the corallites. Circular calicular protuberance small, but pretty distinct. Pseudo-columella 

 somewhat elevated. Septo-costal radii extremely slender and numerous (about 100), but 

 very unequally developed ; about 50 of them reach almost to the centre, and about half of 

 these appear to bear a rudimentary paliform lobule. Diagonal about 1 inch ; diameter of the 

 calicinal ring about 3 lines. A vertical section shows that the tissue is almost entirely 

 vesicular, and it is only in the parts corresponding to the axis of the visceral chamber that 

 some appearance of vertical striae corresponding to the septa are visible. The transversal 

 undulating lines that are strongly marked in this section are produced by the intermittent 

 mode of growth of the corallum, and correspond to the different surfaces, which become 

 rather dense after each period of activity. They are almost horizontal in the parts corres-. 

 ponding to the visceral chambers, and suddenly rise up in the parts corresponding to the 

 line of demarcation between the adjoining corallites. 



Dudley, Wenlock : Egool and Bellaghaderreen, Mayo (M'Coy). 



Specimens in the Collections of the Geological Society, of the Bristol Museum, of Mr. 

 Bowerbank, and of the Parisian Museum. 



This species is very closely allied to S. typus} but differs from it by its internal structure 

 being more completely vesicular, and by its septa being more closely set. 



3. Strombodes Phillipsi. Tab. LXX, figs. 2, 2a. 



Acervulaiua Baltica, Phillips, Palseoz. Foss. of Cornw., Devon, &c, p. 13, pi. vii, fig. 18 e, 



1841. 

 Actinocyathus Piiillipsii, TfOrhigny, Prodr. de Paleont., vol. i, p. 108, 1850. 

 Strombodes Phillipsi, Milne Edwards and Jules Haime, Pol. Foss. des Terr. Palseoz. 



(Arch. duMus., vol. v), p. 429, 1851. 



Corallum much resembling the preceding ones, but differing from them by the existence 

 of well-characterised paliform lobes. The circular elevation corresponding to the limits of 

 the true calice, is also much larger in proportion to the breadth of the corallite, and the 

 septa are less numerous. 



Wenlock. Collection of Professor Phillips. 



4. Strombodes diffluens. Tab. LXXI, figs. 2, 2a. 



Acervulaiua Baltica (pars), Lonsdale, in Murchison, Silur. Syst., pl.xvi, figs. 8, 8a, 1839. 

 Strombodes diffluens, Milne Edwards and Jules Haime, Pol. Foss. des Terr. Palseoz. 



(Arch, du Mus., vol. v), p. 431, 1851. 



1 See tab. lxxi, fig. 1. 



