14 



BRITISH FOSSIL CORALS 



6. Thecosmilia Martini, E. de From} PI. X, figs. 6—9. 



The corallum is bush-shaped, and is formed by dichotomous cylindrical corallites, 

 which are covered with a strong folded and complete epitheca. 



The corallites separate rapidly, and remain free for some distance before fissiparoiis 

 growth occurs again. 



The dissepiments are very developed, and are inclined. 



The calices are circular, or shghtly oval. 



The septa are very thin and distant. There are thirty-two large septa, one half of 

 which reach the centre, and there are forty-eight small, or rudimentary septa. 

 The calices are about fths inch in diameter. 



Localities. Brocastle, Ewenny, Cowbridge. In the Collection of Charles Moore, 

 Esq., F.G.S., Bath. 



This species is distinguished by its size, high septal number, and highly developed 

 endotheca. 



In the British specimens the septa are stouter, and the calices are often larger than in 

 the French ; moreover the larger septa are often raised to the number of forty-eight. The 

 rudimentary septa are not shown in M. Martin's plate. 



The localities whence the species has been derived have been the middle and upper 

 beds of the Zone of Ammonites Moreanus, at Semur, and Vic de Chassenay Cote d'Or. 



It is found in the limestone of Charleville, with Ammonites bisulcatus, in the sand- 

 stone containing Ammonites bisulcatus, at Saul, and in the Hettangian sandstone con- 

 taining Ammonites angulatus. The species had thus a considerable range both in space 

 and time ; and it followed the usual habit of widely wandering species, in varying from 

 the true specific type. 



7. Thecosmilia Michelini, Terq. et Piette? PI. VII, figs. 10—13 ; and PI. X, 



figs. 10—14. 



The corallum is bush-shaped, and is foraied by numerous, close, dichotomous, sub- 

 cyUndrical, long and slender corallites, which are surrounded with a thick, folded, smooth, 

 complete, and persistent epitheca. 



'I'he calices are nearly on the same level, are rounded or oval, and the fossa is not 

 very deep. The septa are forty in number, and are alternately large and small. 



The endothecal dissej)iments are very close. 



1 iVIartin, 'Pal. Sirat. de I'lnfra-Lias,' 1860, pi. viii, figs. 8, 9. 



2 ' Le Lias Infeiieur de Test de la France,' p. 127, pi. xvii, figs. 7, 8. 



