CORALS FROM THE MOUNTAIN LIMESTONE. 201 



conical and the columella small. L. affine is remarkable for the turbinate form of the 

 young corallites, the existence of a well-marked septal fossula, and the abundance of the 

 interseptal vesicles. The coexistence of these characters distinguishes it sufficiently from 

 all the other species. 



13. Lithostrotion Phillipsi. Tab. XXXIX, figs. 3, 3a. 



Lithodendron fasciculatum, Keyserling, Reise in Petsch., p. 170, pi. iii, fig. 2, 1846. 



(Not Phillips.) 

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



p. 439, 1851. 



Corattum fasciculate, much resembling L. Martini^ but differing from it by the 

 frequent coalescence of the corallites, which unite laterally, so as to form small rows, 

 somewhat as in the Halysites. There appears to be about 30 septa. Columella somewhat 

 compressed. Diameter of the calices about 4 lines. 



Found in Ireland and in Russia. The specimen figured in this Monograph belongs to 

 the collection of Mr. Stokes. 



The flexuous form of the corallites, and their mode of partial union by means of 

 longitudinal sutures, distinguish this species from all the other fasciculate Lithostrotions. 



14. Lithostrotion (?) Derbiense. 



Sttlastrea irregularis, M'Coy, Ann. and Mag. of Nat. Hist., 2d ser., vol. iii, p. 9, 1849. 

 Lithostrotion (?) Derbiense, Milne Edwards and Jules Haime, Pol. Foss. des Terr. Palaeoz., 



p. 445, 1851. 

 Sttlaxis irregularis, M'Coy, Brit. Paleeoz. Foss., p. 101, pi. iii a, fig. 5, 1851. 



This fossil is very imperfectly known, having been found only in a very bad state of 

 preservation. The Corallites are irregular and bent in zigzags ; the Calices are polygonal ; 

 the septse flexuous, about 30 in number, rather unequal in size alternately. Tabula 

 broad and almost horizontal ; exterior zone accompanied by two or three rows of vesicular 

 dissepiments. Diameter of the corallites 2 lines. Found in the carboniferous limestone 

 of Derbyshire. 



15. Lithostrotion major. 



Stylaxis major, M'Coy, Ann. and Mag. of Nat. Hist., 2d series, vol. iii, p. 120, 1849. 



— Milne Edwards and Jules Haime, Polyp. Foss. des Terr. Palaeoz., 



p. 454, 1851. 



— M'Coy, Brit. Palseoz. Foss., p. 101, pi. iii a, fig. 4, 1851. 



1 See tab. xl, fig. 2. 



