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 species 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 inclusa. Conical, involved in flint. Guettard, Mem. 



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

 p. 177. 

 Found in Artois. 



Dactylopora. A lapideous free polypifer, of a cylin- 

 dricallv 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. 



.D. 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. 



