44 PEOF. p. MARTIK DTJJ^CAN's EEYISION 01" THE 



the eostae. Calices deep and widely open, witL. four cycles of 

 septa and a single crown of pali. Columella large, composed of 

 numerous trabeculse. Gemmation alternate. 



Distribution. — Becent. Off Eio de la Plata, 600 fms. 



G-enus Haplohelia, Beuss, "Anth. und JBryoz. des Mainzer Ter- 

 tidr.,'' Sitzungsb. der Kais. ATcad. der Wiss. Wien, 1865, 

 p. 202. 



Colony branching. Calices on one side of the stem. Columella 

 small, papillary. Septa in three cycles, and papillose pali before 

 the primaries and secondaries. Costse as long lines of long gra- 

 nules with intermediate depressions running along the whole 

 branch. 



Bistrihution. — Fossil. Miocene : Europe. 



IV. Alliance PROHELIOIDA. 



Oculinidae with branched espalier-like colonies. Corallites projecting 

 and twisted. Columella styliform. No pali. Septa entire. Ccenen- 

 chyma well developed. 



Genus Prohelia, E. de Fromentel. 

 Genus absorbed: — Stylangia. 



Genus Peohelia, F. de Fromentel, Introd. a V etude des Polyp, 

 foss. p. 177 (1861). 



Syn. Stylangia, E. de Erom. 



Colony branched, espalier-like. Calices projecting, placed in 

 two parallel series along the sides of each branch, and all are 

 directed forwards ; they spring from the posterior part of the 

 branches and twist to the right or left to come to the front. 

 Columella styliform. Septa entire. Costse rudimentary. Coenen- 

 chyma very developed, compact and strongly granulated. 



Distribution. — Fossil. Jurassic and Cretaceous : Europe. 



This genus absorbs, according to M. de Eromentel, his genus 

 Stylangia. 



V. Alliance STYLOPHOROIDA. 



Oculinidae with arborescent, palmate, or incrusting colonies. Septa 

 few, 10 or 12 or 24, unequal. Columella styliform. Coenenchyma sub- 

 compact, compact, or cellular, granular. Costae developed, short or absent. 

 Dissepiments present. Gemmation irregular. 



