44 BRITISH FOSSIL CORALS. 



4. SoLENASTR^A GEMMANS, Buncaii. Plate VI, figs. 1 — 7. 



■ The corallura is tall, its base is small, and the caliciilar surface is very irregular. 



The corallites are very unequal, they are sometimes crowded and for the most part are 

 separated by canienchyma ; they are not very exsert, as a rule, but many pass up above 

 the level of the common coenenchyma and exhibit their vrall marked with small 

 costse. 



The exotheca is dense, and resembles layers of membranous epitheca more than a cellular 

 exotheca. It is found here and there only, so that much of the wall of many corallites is 

 free. The exotheca spreads across from corallite to corallite in wavy horizontal layers, and 

 the costse are hidden by it. But where the exotheca is wanting the costae vary greatly 

 in their size and development.^ 



The calices are irregular in shape, size, and distance ; the fossa is shallow, and the 

 columella is rudimentary. The calicular margin is rather blunt. The septa are long, 

 delicate, very ragged on their sides, from their connection with the endotheca, and but 

 slightly granular.- There are four cycles and six systems ; the primary and secondary septa 

 extend Vi^ell inwards, and their ends, which are occasionally enlarged, are connected by 

 ragged and irregular processes ; the tertiary are smaller ; and the septa of the fourth and 

 fifth orders are almost rudimentary. Sections of corallites show the wall to be mode- 

 rately thick. 



The costaj are unequal, and are either plain, short and rounded, short and monili- 

 form, short and bluntly dentate, or even almost vesicular. They are rudimentary when 

 covered by the exotheca. 



The endotheca is very abundant and highly inclined.' The gemmation is pecuhar, and 

 causes the species to resemble in its growth some of the Cladacoracem .• the bud separates 

 widely from the parent, and then passes upwards and soon gives forth a bud which takes 

 the same course. 



Height of corallum several inches. Diameter of corallites ^'oth inch. 



Locality. — Brockenhurst. In the collection of Frederick Edwards, Esq., F.G.S. 



5. SoLKNASTR^A Beyrichi, Diinccm. Plate VI, figs. 8 — 13. 



The corallum is massive, short, and has a very irregular calicidar surface. The 

 corallites are short, and widen out rapidly from a comparatively small base. 



The calices are large, very irregular in shape, generally close, and they are separated 

 by the cccnenchyraal exotheca ; the fossa is shallow, the columella is rudimentary, the wall 

 at the margin is stout, and the septa are thin, often wavy, and rugged laterally. 



' Plate VI, figs. 2, 3, 4. ° Plate VI, (ig. 7. ^ Plate VI, fig. ;. 



