28 DIASTOPORID.^. 



1. DIASTOPORA, Johnst. 



Zoarium aduate, discoid or flabelliform , centric or excentric ; 

 margin entire or lobed ; cells, towards the centre, wholly immersed, 

 usually suberect and partially free towards the margin ; mouth 

 elliptical or suborbicular, horizontal or oblique. 



" Diastopores simples," M.-Edio. I. c. p. 39. 



Diastopora, Johnston ; Bh. I. c. p. 113. 



Diastopora (pars), Lama:., 31.-E(hc., Blainville, lieuss, Ilagenow, 



Michi^Un, JD'Orbif/tii/, Stnitt. 

 Tubulipora (sp.), Johnst., Auct. 



1. Diastopora simplex, Bk. (Plate XXIX. figs. 3, 4.) 



Zoarium thin, papyraceous, ' orbicular or irregular; cells deeply 

 and entirely immersed ; mouth elliptical, nearly even with the 

 surface ; surface coarsely punctate ; no adventitious tubules. 



Diastopora simplex, Bh. I. c. p. 113, pi. sx. fig. 10 ; Smiti, 1. c. p. 396, 



pi. viii. figs. 7, 8. 

 Diastopora obelia (pars), Johnst., Auct. 



Hah. Arctic Sea ; coast of Finmark (Smitt) ; Macgilligan, Ireland 

 (17. Thomps.); Beaufort Dyke, 110-14.5 fathoms (Cajd. Beechey, 

 R.N.). 



2. Diastopora obelia, Johnst. (Plate XXVI.) 



Zoarium adnate, usually slightly raised in the middle (or umbili- 

 cate), orbicular or of irregular outline ; cells produced, partially 

 free and erect ; surface very finely punctate ; a small adventitious 

 tubule rising from the back of some of the cells. 



Tubulipora obelia, Johyist. 1st ed. p. 269, pi. .38. figs. 7, 8 ; Couch, 



Corn. Faun. p. 108. 

 Diastopora obelia,' Johmt. 2nd ed. p. 277, pi. 47. figs. 7, 8 ; Sars ; 



Landsb. ; Alder; Si neks ; Nonnan; Smiit (1865), p. 10, pi. iv. 



figs. 15, 16. 

 Diastopora hyalina (var. a. obelia), Smitt (1866), p. 396, pi. viii. 



fig. 7-12. 

 Diastopora latomarginata, Smitt, ih. p. 397 ; ? D'Orhiqny, Pal. Fran(;. 



p. 827, pi. 758. figs. 10-12. 



Hah. Coast of Britain (ubique), on shell and stone ; Guernsey ; 

 Jersey {Norman) ; Xorth Sea and Arctic Ocean (Smitt) ; Coast of 

 Norway (Loven, Sars) ; Spitzbergen, on Laminaria (Smitt). 



3. Diastopora patina, Lamk. (Plate XXIX. figs. 1, 2, 

 Plate XXX. fig. 1.) 



Zoarium, when mature, discoid, circular, cupped ; central cells 

 immersed and usually closed ; marginal ones erect and open, usually 

 disposed in irregular wavy lines radiating from the centre. 



Tubulipora patina, Johnst. I. c. p. 266, pi. 47. figs. 1-3 ; Gosse, Mar. 



Zool. part 3, p. 8. fig. 1 (uec 3Iilne-Edicards) ; Lamarck. 

 Tubulipora bellis, W. Thomps. 



