320 ESCHARIDiE. 



Localities. South Devon, rare ; Polperro, between 

 tide-marks ; Cornwall, 40 fathoms ; Ilfracombe, in clefts 

 on the Capstone ; Guernsey, about 30 fathoms (T. H.) : 

 Scarborough (Bean) : Northumberland, frequent between 

 tide-marks (Alder) : St. Andrews, on roots of Laminaria 

 digitata and stones near low-water mark, rather abundant 

 (Dr. Mlntosh) : Wick and Peterhead, plentiful (C. W. 

 P.) : Scotland, west (Dr. Landsb.) : Shetland, tide-marks 

 and shallow water (A. M. N.) : Dublin coast (Miss Ball). 



Geographical Distribution. Roscoff (Joliet) : Adri- 

 atic, on mussel-shells, rare (Heller) : Greenland (Liit- 

 ken). 



Range in Time. Scotch Glacial deposits (Geikie) : 

 Paleolithic (A. Bell). 



ii. With a raised secondary orifice. 

 Genus PORELLA*, Gray. 



Der. From ttojoos, an opening. 



Celi.epora (part.), Fleming. 



Eschar A (part.), Sars: Busk: Alder: Smitt : &c. 



Hemeschara (part.), Norman, &.c. 



Lepralia (part,), Busk, &c. 



PoRELLA, Smitt. 



(teneric Character. Zocecia with the primary orifice 

 semicircular ; secondary {or adult) orifice elongate, in- 

 versely suhtriangular or horseshoe-shaped, inclosing an 

 avicularium, usually with a rounded mandible. Zoarium 



* Gray introduced this name, with a very insufBcient diagnosis, for a 

 genus of which he made Esck. cervicornis, Johnst., the type ; and it will be 

 convenient to retain it for the group to which the latter species belongs. 

 Smitt, in his ' Critical Catalogue,' adopts it for a genus in which he places 

 P. concinna and P. lavis ; but P. cmnp'essa he relegates to his genus Eschara. 



