CORALS FROM THE SILURIAN FORMATION. 269 



7. MONTICULIPORA LENS. 



Nebulipora lens, M'Coy, Ann. and Mag. of Nat. Hist., 2d series, vol. 6, p. 283, 1850. 

 — — M'Coy, Brit. Palseoz. Foss., p. 23, pi. i c, fig. 7, 1851. 



" Corattum forming lenticular masses, averaging 10 lines in diameter, and 1^ lines 

 thick in the middle, gradually thinning to the edge; base slightly concave, with small 

 concentric wrinkles ; upper surface evenly convex ; clusters of large cells rounded, flat, or 

 slightly concave, about 1 line in diameter, and usually a little more than their diameter 

 apart (averaging from sixteen to twenty cells between one centre and another) ; smaller 

 tubes averaging eight in one line, larger tubes of the clusters averaging four or five in one 

 line; two inter-diaphragmal spaces equal the diameter of the tubes; apparently two 

 irregular, close rows of connecting pores on each face of each tube (?). 



" Caradoc sandstone of Horderly West ; schists of Moel Uchlas ? Pont y Glyn, Diffwys, 

 near Corwen ; Cwm of the Cymmerig, Bala." M'Coy, op. cit. 



Stenopora? granulosa, M'Coy, Brit. Pakeoz. Foss., p. 26; Ceriopor a granulosa, 

 Goldfuss, Petref. Germ., vol. i, tab. lxiv, fig. 13; is a fossil coral from Dudley, which 

 appears to belong to the class of Bryozoa. 



4. Genus Labecheia. 1 



1. Labecheia conferta. Tab. LXII, figs. 6, 6a, 6b, 6c. 



Monticularia conferta, Lonsdale, in Murcliison, Silur. Syst., p. 688, pi. xvi, fig. 5, 1839. 

 Labecheia conferta, Milne Edwards and Jules Haime, Pol. Foss. des Terr. Palaeoz. (Arch. 

 duMus., vol. v), p. 280, 1851. 



Corallum massive, or forming lamellar expansions, which are often incrustating. 

 Common basal plate covered with a thick, wrinkled epitheca ; upper surface flat or sub- 

 mammillar, and covered with small granular conical tubercles, which appear to rise from the 

 edge of the walls ; calices confluent and not distinct ; visceral chambers filled up with 

 complete, horizontal, closely set tabulse, and presenting quite rudimentary septa. Walls 

 thick, and not perforated. Breadth of the visceral chamber about a quarter of a line. 



In some specimens the marginal mural tubercles are ranged in regular series, so as to 

 assume the appearance of small ridges. 



1 See Milne Edwards and Jules Haime, Pol. Foss. des Terr. Palaeoz., p. 279, 1851. 



36 



