36 F. A. SMITT, 



altered and of the justly typical form of this species. This aperture, in the Gemelli- 

 pora eburnea, is truly escharine; otherwise it has its corresponding parts in the above 

 described Mamillopora cupula, what will best be understood, if we imagine the proximal 

 part of that aperture to be reduced almost to the extent of the sinus of the proximal 

 margin, whereby the lateral sinuses are to be less marked between this and the con- 

 strietion for the articulation of the operculum. Thus, the aperture of Gemellipora (fig. 

 156), through that reduction of the proximal part, will assume a more circular shape. 

 The pores in the wall of the zooecia are very scarce; otherwise they resemble the same 

 punctuation in the Crisice. 



As to the elongated form of the creeping state, it is worthy of notice, how it 

 shows the greatest similarity to the cretacean Hippothoa elegans, as described by D'Or- 

 bigny *), which, moreover, in the colonial form reproduces the erected state of Gemelli- 

 pora eburnea, if this be thought to be reduced into a uniserial constitution. But for 

 the identification of the species, the cretacean fossil, I think, must be examined again. 



Gemellipora eburnea seems to be a deep-sea form. Pourtales has taken it from 

 the depths of 120 — 170 fathoms, growing on Cellepora margaritacea, on pieces of dead 

 shells and on stones. 



With almost the same form of the zocecial aperture, this species, among the 

 Floridan Bryozoa, has its nearest relation to the 



Gemellipora lata (Pl. VII, fig. 157), 



what species also seems me to be new for the science. 



Char. spec: Zooecia lata, frontem prtebent modice ventricosam, poris sat magnis 

 pertusam, aperturam (cujus låtit. circ. = 0,13 mm.) rotundate quadrangularem, margine 

 proximali latissime sinuatam, margine laterali aliquantulum incrassato circum-scriptam, 

 aream triangularem, depressam, lateribus aliquanto incrassatis limitatam, proximaliter 

 pone aperturam positam praabent. Avicularia rotunda, verrucarum forma, quorum 

 apertura rotunda latitudinem fere 0,1 mm. prsebet, inordinatius supra confinia zooecio- 

 rum distributa sunt. 



Hab.: Pourtales hane speciem, una cum Vincularia abyssicola et forma serpente 

 speciei sequentis, JSfulliporam obducentem e prof. 68 orgyarum sustulit. 



Of this species, I have only seen one small colony, growing on a Nullipora, that 

 was brought up by Pourtales from a depth of 68 fathoms. It has a yellowish colour, 

 with the zooecial apertures, through their covering membrane and Operculum, of a 

 darker greenish-yellow tint. As to their size, the zooecia are rather of the greater ones 

 of the more regular Escharines; the breadth of their apertures, at their middle, I have 

 measured to be about 0,13 mm. A comparison between the figures 157 and 152 which 

 are delineated at the same enlargement, will show the difference, in this respect, from 

 the preceding species. 



The form of the zooecial apertures I have named circularly quadrangular, because 

 the constriction at the articulation of their operculum is less marked, so that their 



') Pal. Franc, Terr. Gret., vol. V, p. 384, pl. 711, figs. 1—4 



