90 



PEOF. P. MARTIN DTJNCAN's EEYISION OP THE 



Grenus Leptoria, Milne-JEdwards Sf Jules Haime^ Hist. Nat. 

 des Corall. vol. ii. p. 405 (1857). 



Colony massive, very largely fixed. Corallite series unite by 

 their walls, and the ridges at tlie surface are always simple, usually 

 thin. The valleys are long, straight, or very sinuous, or both in 

 the same colony. Calicinal centres perfectly indistinct. Columella 

 lamellar, lobed, and projects where free in the series. The septa 

 are slightly exsert, unite to the columella by means of trabecula?, 

 and their dentations are small and irregular. Endotheca exists. 



Distribution. — Fossil. Cretaceous : Europe. Eocene, Oligo- 

 cene, Miocene ; Asia. — Becent. Indian Ocean, Pacific, Seychelles, 

 Eodriguez, Eed Sea. 



Genus MzEANDRASTRiEA, MUne-Fdivards Sf Jules Haime^ Hist. 

 Nat. des Corall. vol. ii. p. 452 (1857). 

 Colony massive, convex. Corallites in series united by their 

 costae or by their walls. Corallite ridges (or collines) at the surface 

 rather broad, with or without a delicate groove. Valleys nume- 

 rous, short. Calicinal centres distinct, but united by septo-co&tse. 

 Columella small, lamellary. 



Distribution. — Fossil. Cretaceous : Europe. 



Grenus 'Bjiacky'mma:ni)'rina, Duncan. 

 Syn. Coeloria (pars), Ehr. 



Colony large, low, attached, but extending beyond fixed point, 

 slightly convex above. Corallites in long series, mainly radia- 

 ting from the centre. Wall between the series rudimentary, 

 discontinuous, and consisting of series of knob-like projections. 

 Upper surface of ridges with exsert septo-costse, spined and 

 dentate, the upper wall-projections being visible. Calicinal 

 centres not distinct. Columella small, essential, and receiving 

 trabeculsB from the septal ends, projecting as little processes 

 between the septal ends. Septa stout, short, exsert, angular 

 in outline. Endotheca well developed, and often extending 

 between the discontinuous parts of the walls. Common plateau 

 without a true wall, and with a strong folded epitheca, from 

 which spring the septa and columella. 



Distribution. — Becent. Eed Sea, Mergui, Ascension. 



Grenus Stelloria, d'Orbigny, Note sur les Folyp. foss. 

 p. 9 (1849). 



Colony massive. Corallites in series united by their walls, 



