208 BRITISH FOSSIL CORALS. 



arched, slightly inclined inwards, broader than high, and bear on their surface small 

 rudiments of costal prolongations. A horizontal section usually passes through three of 

 these vesicles in the space comprised between the two walls, and shows that the dissepi- 

 ments in the inner zone are simple, almost horizontal, or slightly arched, and placed at 

 about half a line apart. 



Found in Derbyshire, in Russia, and in North America. Specimens are in the 

 collection of M. de Verneuil. 



This species much resembles L.floriformis} but differs from it by its columella being 

 less stout and less prominent, and by its rudimentary costal radii. It differs from 

 L. Brown? by the unequal development of its septa, and from L. rugose? and L. duplicated 

 by the fasciculate forms of these two latter species. 



3. Lonsdaleia rugosa. Tab. XXXVIII, fig. 5. 



Lonsdalia rugosa, M'Coy, Ann. and Ma?, of Nat. Hist., 2d series, vol. iii, p. 13, 1849. 



— — Milne Edwards and Jules Haime, Pol. Foss. des Terr. Palseoz., p. 461, 



1851. 



— — M'Coy, Brit. Palseoz. Foss., p. 105, pi. iii B, fig. 6, 1851. 



Corattites in general free laterally, sub-cylindrical, having very strong circular growth 

 swellings, and covered with a very thick epitheca. Columella broad. Septa thin, and 

 almost equal, about 10. Diameter of the Corallites very variable; — the largest about 

 8 lines. 



Found at Mold and Corwen. Specimens are in the collections of the Museums of 

 Practical Geology, of Cambridge and of Paris. 



This species differs from L. Bronni, 5 L. Jloriformis, 6 and L. papillata, 7 by the 

 tendency of the Corallites to remain free laterally ; and from L. duplicata,* which it 

 resembles in that respect, by the irregular tumefactions of the surface of the walls of the 

 corallites. 



1 See tab. xliii, figs. 1, 2. 



2 Milne Edwards and Jules Haime, Polyp, des Terr. Palseoz., tab. xi, fig. 1. 



3 M'Coy, Brit. Palseoz. Fossils, p. 105. 



4 Lonsdalia crassiconus, M'Coy, Ann. and Mag. of Nat. Hist., 2d ser., vol. iii, p. 12. Erismatolithus 

 duplicatus, Martin, Petiif. Derb., pi. xxx. 



5 Milne Edwards and Jules Haime, Polyp. Palaeoz., tab. xi, fig. 1. 



6 See tab. xliii, figs. 1,2. 7 Milne Edwards and Jules Haime, op. cit., tab. xi, fig. 2. 

 8 Lonsdalia crassiconus, M'Coy, Ann. of Nat. Hist., 2d series, vol. iii, p. 12. 



