lxx BRITISH FOSSIL CORALS. 



22. Genus Clisiophyllum. 



(Pars) Dana, Exploring Exped., Zoophytes, p. 361, 1846. 



Corallum simple, turbinate. Septa well developed, and rising towards the centre of 

 the calice so as to form a spurious columella, but not twisted. 



Typ. sp., Clisiophyllum Danianum, nob. 



23. Genus Aulophyllum. 



Corallum simple. Septa well developed. A double mural investment; the interior 

 wall dividing the visceral chamber into two portions — one central and columnar, the other 

 exterior and annular. No columella. Tabula but little developed. 



Typ. sp., Aulophyllum prolapsum ; Clisiophyllum prolapsum, M'Coy, in Ann. and Mag. of Nat. Hist., 

 2d series, vol. iii, p. 3. 



24. Genus Acervularia. 



Schweigger, Handb. der Naturg., p. 418, 1820. 



Corallum composite, increasing by calicular gemmation. Corallites provided with a 

 double mural investment ; the inner wall disposed as in the preceding genus. Septal 

 apparatus well developed between the outer and the inner walls, but much less so in the 

 central area. No columella. Tabula not well developed. 



Typ. sp., Acervularia Rcemeri ; Astrea Hennahi, Rcemer, Verst. der Hartzgeb., tab. ii, fig. 13 (not 

 Lonsdale). 



25. Genus Strombodes. 



(Pars) Schweigger, Handb. der Naturg., p. 418, 1820; Goldfuss, Petref. Germ., vol. i, p. 62, 1826; 

 Acervularia, Lonsdale, Sil. Syst., p. 689, 1839; Arachnophyllum, Dana, Zooph., p. 360, 1846; Strombodes 

 and Actinocyathus, D'Orbigny, Prod, de Paleont. stratigr., vol. i, p. 107, 1849. 



Corallum composite, increasing by calicular gemmation. Corallites constituted prin- 

 cipally by a series of superposed, invaginated, infundibuliform tabula, united by ascending 

 trabiculse, so as to form a columnar mass. Calices pentagonal, well circumscribed, and 

 completely covered with the septal radii. Outer walls not well developed ; the inner 

 mural investment rudimentary. 



Typ. sp., Strombodes pentagonus, Goldf., Petref. Germ., vol. i, tab. xxi, fig. 3. 



26. Genus Phillips astrea. 



D'Orbigny, Note sur des Polypiers fossiles, p. 2, 1849. 



Corallum composite, resembling Strombodes, but differing from them by the septal 



