204 BRITISH FOSSIL CORALS. 



1^ line; depth one half the diameter. A vertical section shows that the walls are some- 

 what indistinct ; the visceral chambers are closed by large, concave, somewhat irregular 

 tabulae, and that the vesicles occupying the intercostal loculi are small, irregular, twice as 

 high as they are broad, and arranged pretty regularly in horizontal rows. 



Found in Derbyshire, and at Corwen ; and, according to Martin, at Winster. Spe- 

 cimens are in the Collections of the Museums of Practical Geology, of Cambridge and of 

 Paris. 



This species differs from P. Verneuili, 1 by its septo-costal radii being very slender, 

 and somewhat unequal, and it appears to differ from P. tuberosa 2 by its calices not having 

 prominent edges, and by the horizontal arrangement of the series of interseptal vesicles, 

 which, in this last-mentioned fossil, appear to form concave or flexuous rows. We are, 

 however, not quite sure that these differences may not be accidental. 



2. Phillipsastr/ea tuberosa. 



Sarcinula tuberosa, M'Coy, Ann. and Mag. of Nat. Hist., 2d series, vol. iii, p. 124, 1849. 

 Phillipsastrea tuberosa, Milne Edwards and Jides Haime, Pol. Foss. des Terr. Palseoz., 



p. 449, 1851. 

 Sarcinula tuberosa, M'Coy, Brit. Palseoz. Foss., p. 110, pi. iii b, fig. 8, 1851. 



Calices prominent, mammiliferous, and in general placed very distant from each other, 

 but irregularly so. Septo-costal radii (32) extremely thin, confluent, and flexuous 

 externally, but not strongly geniculated. Intercostal dissepiments subpolygonal, twice as 

 broad as they are high, somewhat unequal, and appearing to form concave or flexuous rows. 

 Diameter of the Calices, scarcely 2 lines. 



From the carboniferous limestone of Derbyshire. Specimen in the Cambridge Museum. 



Sub-Family AXOPHYLLIN^E, 3 

 1. Genus Petalaxis, (p. lxxi. 4 ) 



Petalaxis Portlocki. Tab. XXXVIII, figs. 4, 4a. 



Stylaxis Portlocki, Milne Edwards and Jules Haime, Pol. Foss. des Terr. Palseoz., p. 453. 

 1851. 



1 Milne Edwards and Jules Haime, Polyp. Palseoz., p. 447, tab. 10, fig. 5. 



2 Sarcinula tuberosa, M'Coy, Ann. and Mag. of Nat. Hist., 2d series, vol. iii, p. 124. 



3 Milne Edwards and Jules Haime, Pol. Foss. des Terr. Palseoz., p. 452. 

 * Under the name of Nematophyllum. 



