FAMILIES AlfD QENEEA OF THE MADEEPORAEIA. 



189 



Distribution. — Fossil. Miocene of West Indies and France. — 

 Becent. Australian and Chinese seas, Indian Ocean. 



Grenus GtONIopoea, Quoy Sf Gaimard^ Voi/. de V Astrolabe, Zooph. 

 p. 218 (1833). 



Colony attached or free, lobed or hemispherical, or in tall blunt 

 cylindrical masses. Corallites with distinct trabecular walls join- 

 ing those of their neighbours, without intermediate tissue. Ca- 

 lices unequal in size, and shallow or deep, pentagonal. Septa 

 j)rojecting but little in the upper part of the calices and ragged, 

 extending towards the columella as porose trabecular laminae. 

 Columella well developed, spongy. No pali. Gremmation between 

 the calices. Endotheca exists. 



Distribution. — Becent. Eed Sea, Indian Ocean, Pacific. 



Grenus Lithae^a, Milne- Edwards Sf Jules Haime, Comptes 

 Bendus, t. xxix. p. 258 (18di8), amended. 



Colony low, free or incrusting, lobed, or dendroid, or discoid, 

 with an imperfect or well-developed epitheca. Corallites with 

 trabecular porose walls adherent to, or fused with those of their 

 neighbours. Calices polygonal or irregular. Septa well deve- 

 loped, and subperforate and echinulate. Columella trabecular, 

 and formed by the septal ends. No pali. 



Distribution. — Fossil. Cretaceous (Upper): Europe. Eocene: 

 Europe, Sind, Java. Oligocene : Europe. Miocene : Erance. 



The septa approach those of the Astraeid^e, and the genus 

 is closely allied to the recent Goniopora. 



Some comparatively late researches on the next genus have 

 modified the generic diagnosis, and have given a higher distribu- 

 tional range to the species. 



Grenus Peotae-^a, Milne-Edwards Sf Jules Uaime, Hist. Nat. 

 des Corall. vol. iii. p. 184 (1860), amended. 



Colony incrusting and massive. Corallites polygonal, with 

 simple perforated walls, which at the calicular surface are nar- 

 rower than the calice by one half, and are ornamented with 

 points. Calices shallow. Septa 6-12 to 24 in number, pass a 

 little way in and are sublamellary and dentated. No columella. 



Distribution. — Fossil. Silurian : America. Devonian : Europe. 



