71 



table, as have shown its right to be considered as of this 

 genus, and probably as Alv. suborbicularis. 



Ocellaria, — A lapideous polypifer, expanded in a mem- 

 branous form ; variously convoluted and rather infundi- 

 buliform ; with an arenaceous surface, porous on both sides ; 

 pores cylindrical, in quincunx order, with a solid axis in a 

 raised centre. 



These bodies have the appearance of an eschara, or a 

 retepora ; but are distinguished particularly by the solid 

 central axis which is raised to the orifice of each pore, and 

 forms there a sp6cies of papilla. 



There are but two species, both of which are fossil. 



1 . ■ Ocellaria nuda. — Infundibuliform, expanded and branching in 



various ways. — Ramond Voyage au Mont Perdu, p. 128, PL ii. 

 fig. 1, and p. 345 : Bulletin des Sciences, No. 47, p. 177. 

 Found in the limestone of Mount Perdu in the Pyrenees. 



2. Ocellaria inchisa. — Conical, involved in flint. — Guettard, Mem. 



vol. iii. PI. xli ; Ramond, PI. 2, fig. 2 ; Bulletin des Sciences, 

 p. 177. 

 Found in Artois. 



Dactylopora, — A lapideous free polypifer, of a cylin- 

 drical ly clavated form, with a perforation in the narrower 

 extremity. The surface reticulated with rhomboidal meshes, 

 the network itself porous. 



It differs from retepora, in being a loose, simple poly- 

 pifer, without lobes, ramifications or frondescence. It pos- 

 sesses an opening essential to it. The net-work is double, 

 interior and exterior, which unite near the opening. 



Z>. Cylindracea. 

 1. Fossil. Reteporite. — Bosc Journal de Physique, Juin 1806. 



FORAMINATED POLYPIFERS. 



Stony, solid, and internally compact ; with perforating 

 or tubular cells not furnished with laminae. 



