CORALS FROM THE MOUNTAIN LIMESTONE. 155 
2. MicHeninta TEenuisEpTa. Tab. XLIV, figs. 1, la, 14. 
CALAMOPORA TENUISEPTA, John Phillips, Illust. of Geol. of York., vol. ui, p. 201, pl. ui, 
fig. 30, 1836. 
MIcHELINIA TENUISEPTA, De Koninck, An. Foss. des Terr. Carb. de Belg., p. 31, pl. c 
fig. 3, 1842. 
— — Michelin, Icon. Zooph., pp. 83 and 254, pl. xvi, fig. 3, 1843. 
Favosrtes (MICHELINEA) TENUISEPTA, M‘Coy, Syn. Carb. Foss. of Ireland, p. 193, 1844. 
MicunLinea GLomERAtA? M‘Coy, Ann. and Mag. of Nat. Hist., 2d Series, vol. iii, p. 122, 
1849. 
FavosITEs TENUISEPTA and MIcHELINIA TENUISEPTA, D’Orbigny, Prod. de Paleont., vol. i, 
p. 160, 1850. 
MIcHELINIA TENUISEPTA, Milne Edwards and Jules Haime, Pol. Foss. des Terr. Paleoz., 
p. 250, 1851. 
MicHELinEa GLoMERATA? M‘Coy, Brit. Paleeoz. Foss., p. 80, pl. iii B, fig. 14, 1851. 
Corallum tall; common basal plate with a strong epitheca, striate transversely, but not 
bearing any radiciform processes. Calices polygonal, unequal in size, and containing 
thirty or forty equally developed septal striae. Zudule very delicate, closely set, much 
blended together, and minutely granulated. 
Height of the corallum 4 inches; diagonal of the calices 3 or 4 lines. 
M. tenuisepta is found in the environs of Bristol, at Masbury, near Mendip, and at 
Bolland ; Professor M‘Coy has also met with it in Ireland; and it exists also on the Conti- 
nent, at Sablé and Juigné, in France, and at Tournay, in Belgium. Specimens are in the 
collections of the Museums of Bristol, of Cambridge, of Paris, &c. 
This species much resembles J/. favosa, by the structure of the visceral chambers, 
but differs from it by the corallites bemg more elongate, and by the common basal 
plate not bearing any radiciform appendices. MM. tenuisepta is also very closely allied 
to M. convexa’ and M. megastoma,’ but its endothecal vesicles are less convex, and it 
never attains the size to which this species usually come. The obliquity or irregular 
arrangement of its tabule distinguish it from JZ, antigua’ and MW. concinna,* in which 
the tabulz are almost horizontal and distinct. J. geometrica’® differs from the above- 
described species by the great regularity of its polygonal calices. 
We refer to this species, but with some doubt, the fossil designated by Professor 
M‘Coy, under the name of Jichelinea glomerata; in the specimen figured by that 
geologist, the common basal plate is worn away, so that it is not possible to ascertain 
1 D’Orbigny, Prod., vol. i, p. 107; Milne Edwards and J. Haime, Polyp. Paleeoz., tab. xvi, fig. 1. 
2 See tab. xliv, fig. 3. 
Dictyophyllia antiqua, M‘Coy, Syn. of Carb. Foss. of Ireland, tab. xxvi, fig. 10. 
* Lonsdale in Geol. of Russia, by Murch., Verneuil, and Keyserling, vol. i, p. 611, tab. a, fig. 3. 
Milne Edwards and J. Haime, Polyp. Paleeoz., tab. xvii, fig. 3. 
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