17C BRITISH FOSSIL CORALS. 



4. Amplexus spinosus. 



Amplexus spinosus, De Koninck, Ann. Foss. des Terr. Carb. de Belg., p. 28, pi. c, 



fig. 1, 1842. 

 Cyathaxonia spinosa, Michelin, Icon., p. 257, pi. lix, fig. 10, 1846. 

 — — VOrbigny, Prod, de Pal., vol. i, p. 158, 1850. 



Calophylltjm spinosum, M'Coy, Brit. Paleeoz. Foss., p. 91, 1851. 



Amplexus spinosus, Milne Edwards and Jules Haime, Pol. Foss. des Terr. Palseoz., p. 346, 

 1851. 



Corallum elongate, cylindro-turbinate, somewhat twisted, acute at its basis, with a 

 rudimentary epitheca and but slightly developed circular accretion swellings. Costal ridges 

 flat, sub-equal, closely set, smooth towards the upper part of the corallum, but in the basal 

 half of this armed with a series of small ascendant spines. Calice rather deep. Septal 

 fossula small. Upper tabula not very broad, especially in young specimens, and some- 

 times protruding a little in the cavity of the calice. Principal septa not numerous, (sixteen,) 

 very thin, very narrow upwards, presenting a concave denticulated edge inwards, slightly 

 bent towards the centre of the corallum, and alternating with an equal number of very 

 small ones. Height of the corallum about 2 inches ; diameter of the calice about 5 lines. 



Found in the black carboniferous shale at Poolwart, Isle of Man, and at Tournay, in 

 Belgium. Specimens are in the collections of the Cambridge Museum, the Paris Museum, 

 the Ecole des Mines, M. de Verneuil, &c. 



This Coral is distinguished from all the other species of Amplexus by the spines which 

 are developed on the surface of the lower part of its wall. 



5. Amplexus Henslowi. Tab. XXXIV, figs. 5, 5a. 



Cyathophyllum ceratites, Michelin, Icon. Zooph., p. 181, pi. xlvii, fig. 3, 1845. (Not 



Goldfuss.) 

 Amplexus Henslowi, Milne Edwards and Jules Haime, Pol. Foss. des Terr. Palaeoz., p. 346, 

 pi. x, fig. 3, 1851. 



Corallum turbinate, not very elongate, not strongly curved, and having but slight 

 circular accretion swellings. Epitheca probably delicate, and when worn off leaving 

 uncovered numerous flat equally developed costse. Calice filled up with extraneous matter 

 in all the specimens examined, but appearing to be deep. Tabula irregularly developed, 

 large, sloping downwards towards the ventral or concave side of the corallum, and reaching 

 almost from wall to wall. Septa appearing to be numerous, narrow, and unequal alter- 

 nately. ^Septal fossula not observable, on account of the filling up of the calice. Height 

 of the corallum in the large specimens 3 inches ; diameter of the calice 2 inches or more. 



