MR. A. W. WATERS ON MEMBRATSTIPORID^. 685 



Membrajstipora tentjirostris, HincTcs. (PI. 47. fig. 7.) 



Membranipora tenuirostris, Hincks, Ann. ^ Mag. Nat. Hist. ser. 5, 

 vol. vi. p. 70, pi. ix. fig. 3 ; Waters, Journ. Roy. Micro. Soc. ser. 2, 

 vol. v.p. 5, pi. xiv. fig-. 41 ; Quart. Journ. Geol. Soc. vol. xlvii. p. 11. 



Membranipora Flemingii, Waters, Ann. ^ Mag. Nat. Hist. ser. 5, 

 vol. iii. p. 122, pi. xiii. fig. 2. 



The Naples and Eapallo specimens liave not the spines at the 

 side figured bj Mr, Hiucks, but there is often a small spine at 

 one side below the ovicell. Instead of a bar across the avicularian 

 chamber, there are two large denticles directed towards one 

 another. This species does not show any signs of suboral glands, 

 nor have I found this structure in any of the Membraniporidae, 

 having cut sections of M. tenmrosfris, M. pilosa, M. inarmata, 

 M. patellar ia, M.jlustroides, Onychocella angulosa. 



There is one large distal pore-chamber and t^vo lateral ones, 

 though when the zooecia are very irregularly placed there may be 

 more, but as a rule it is one rosette-plats to each neighbour. 



Loc. Naples; Eapallo; Adriatic; Queen Charlotte Island; 

 Madeira. Possil : Bartonian of IN", Italy. 



Membranipora sculpta, MacG., var. cfctjllata, nov. (PI. 

 47. fig. 14.) 



Type. Membranipora sculpta, MacG. Tert. Polyz. Viet. p. 36, pi. v. fig. 1. 



Zoarium incrusting. Zooecia irregular, more or less oval, with 

 the proximal edge often straight. Margins thick, sloping in- 

 wards and downwards, granular, slightly crenulated. Avicularia 

 round, vicarious, the upper part raised, forming a kind of cap. A 

 very distinct bar across the avicularium. Ovicells prominent, 

 with a large area. 



This only seems to diflFer from the fossil M. sculpta, from 

 Schnapper Point and Muddy Creek, in not having the avicu- 

 larium sculptured and in having the upper part raised. The 

 chitinous parts are not preserved in the single specimen ex- 

 amined. 



Loc. Charleston, South Island (New Zealand) ; sent by Miss 

 Jelly. 



Membranipora crassimarginata, HincJcs. (PI. 47. fig. 4.) 

 Membranipora crassimarginata, HincJcs, Ann. 8j- Mag. Nat. Hist. ser. 5, 

 vol. vi. p. 71, pi. ix. fig. 1, & ser. 6, vol. viii. p. 86. 



There are specimens from both Naples and Capri, differing, 

 however, from previous descriptions in the character of the 

 ovicells, which are small, cucullate, with a strong thickened 



