326 ESCHARID^. 



wall overlap the ovicell^ and form two rib-like prominences 

 in front (Plate XLVI. fig. 3). On the whole P. concinna 

 must be accounted a variable species; but it is readily 

 distinguishable under all its disguises by the peculiar 

 character of the adult orifice. 



Habitat. On shells, &c., from shallow to deep water. 



Localities. The species is common, and widely distri- 

 buted. Belfast Bay, 20-25 fathoms; ibid., deep water off 

 the Copelands (W. T.) : Isle of Man; Torbay; Guernsey, 

 very abundant; off the Deadman, 60 fathoms (T. H.) : 

 Northumberland, deep-water boats, rare (Alder) : St. 

 Andrews (Dr. M'Intosh) : Antrim, deep water (Hynd- 

 man) : Shetland, 40-170 fathoms ; the Minch (A.M.N.) : 

 Hastings (Miss Jelly) : &c. With fine spatulate avicu- 

 laria, Guernsey (T. H.). Var. a, Shetland (A. M. N.). 



Geographical Distribution. Adriatic, on Serpulee, 

 rare (Heller) : Bahusia ; Finmark (Loven) : Norway 

 (Sars) : Spitzbergen, 20-30 fathoms (Swed. Exped.) : 

 Godhavn, Greenland (Torell) : Gulf of St. Lawrence (Daw- 

 son). Var. a {Belli), Gulf of St. Lawrence (Dawson). 



Kange in Time. Scotch Glacial deposits (Geikie) : 

 Palaeolithic (A. Bell) : Postpliocene beds, Canada (Daw- 

 son) . 



PoRELLA minuta, Norman. 



Plate XXIX. figs. 1, 2 ; Plate XXXVI. figs. 6, 8. 



Lei'ralia minuta, Norman, Shetland Pol., Rep. Br. Assoc. 1868, 308. 

 ?Lepralia cuilopora, Manzoni, Bryoz. cli Castrocaro, 32, pi. iv. fig. 51. 



Zooscia minute, distinct, divided by deep sutures, disposed 

 in regular radiating lines, somewhat wedge-shaped, 

 smooth or granular, strongly areolated round the 



