CORALS FROM THE MOUNTAIN LIMESTONE. 187 



septa forty or fifty in number, rather thick in their outer half, and alternating with an 

 equal number of very small ones. The exterior portion of the corallum very vesicular ; 

 the columellarian area very distinct. Height of the corallum from 3 to 5 inches. Diameter 

 of the calice about 1^ inch or more. 



Found at Oswestry, Derbyshire, and at Vise, in Belgium. Specimens in the Collections 

 of the Museum of Practical Geology, of Bristol, and of Paris. The British specimens 

 communicated to us for the preparation of this Monograph, were not in a sufficiently good 

 state of preservation to be figured. 



C. Keyserlingi differs from all the other species of the same genus, except C. Danaanum, 1 

 by its septa being rather thick, and its walls tumefied ; it differs also from the latter, in 

 having the septa more numerous and more unequal. 



5. Clisiophyllum ? costatum. 



Cyathaxonia costata, M'Coy, Ann. and Mag. of Nat. Hist., 2d series, vol. iii, p. 6, 1849. 

 Clisiophyllum costatum, Milne Edwards and Jules Haime, Pol. Foss. des Terr. Palseoz., 



p. 412, 1851. 

 Cyathaxonia costata, M'Coy, Brit. Palseoz. Foss., p. 109, pi. iii c, fig. 2, 1851. 



This species has been established for a small coral, which appears to be a young 

 Clisiophyllum, and belongs probably to one of the preceding ones, although we are not 

 able to determine its precise specific character. It is conical, with a circular calice con- 

 taining twenty-six septa. It is about 1 inch high, and 3 lines in diameter at the calice. 



Found in Derbyshire, and belonging to the Cambridge Museum. 



6. Clisiophyllum bipartitum. 



Clisiophyllum bipaktitum, M'Coy, Ann. Nat. Hist., 2d series, vol. iii, p. 2, 1849. 

 — — M'Coy, Brit. Palseoz. Foss., p. 93, pi. iii c, fig. 6, 1851. 



" Very elongate, conic, nearly cylindrical, with a diameter of one and a quarter inch, 

 for the greater part of its length ; strongly and regularly striated externally (about five 

 stria? in one fourth of an inch) ; external striae corresponding in number to the radiating 

 lamellae ; in the transverse rough section, the central area is rather more than one third 

 the whole diameter, composed of the edges of confusedly-blended vesicular plates, crossed 

 by a few faint extensions of the radiating lamellae, and divided into two symmetrical 

 portions by a strong median fissure ; the space between this inner area and the outer wall 

 is narrow and regularly radiated with about fifty-eight equal, thin, rather distant 



1 Milne Edwards and Jules Haime, Polyp, des Terr. Palseoz., p. 412. 



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