BRYOZOA 



39 



Megapora hyalina sp. nov. 



(PI. II, figs. i3(î, b, and figure 1 in the ti 



— Megapora hyalina 

 nov. Showing the oral 

 spines, and the small 



Zoarium adnate. Zoœcia hyaline, ovate, with enclosed area the border of which is 

 crenulate. There are on the front of the area two elongate foramina, somewhat irregularly 

 placed, but far from the oral aperture and not near to the crenulated 

 border. The oral orifice is straight on the lower edge and the lower 

 part is raised, so that the proximal part of the operculum, which is 

 darker and thicker than the rest, is directed upwards, as if it were hinged, 

 but there is no calcareous bar between the two parts. The sides of the 

 oral aperture are nearly straight, the complète aperture having much the 

 same shape as that of Lepralia, as the lower part does not extend late- 

 rally. There are six oral spines, and also one, two or even three minute 

 spines on the zoœcium outside the area about half way down. In the 

 first spécimen received, only the pores ofthe small broken latéral spines 

 were seen and the description was first drawn up from one small spécimen 

 on a large stone, on which it was awkwardly placed for examination, but Fig. 1. 

 since the plates were in the lithographer's hands, another spécimen from 

 319 has been sent to me, and on this the oral and minute spines were i ate ral spines. 

 first found. 



This has many characters in common with the northern .17. ringens Busk, in which the 

 operculum readily séparâtes into two parts (PI. III, fig. l3). In sorae spécimens from Shetland, 

 kindly given to me by Canon Norman, I am unable to find any vibracula, and there is 

 no calcareous bar separating the two parts of the operculum as some previous figures seem 

 to indicate. The frontal surface of thèse spécimens is finely granular. Re-examination of 

 M. ringens has not shown any foramina or opesiules. 



Thèse two species are at any rate closely allied, the main différence being that in 

 M. ringens the lower darker part ofthe operculum, or opercular appendage, spreads out laterally 

 (PI. III, fig. i3). There is a relationship with Micropora, and it will be seen, that there is 

 much in common with Setosclla vulnerata Busk. 



M. ringens B. has been found off Shetland and Bergen. 



Habitat. — Exp. Antarct. Belge. 



N° 392, Eel trap I. Lat. 71 i5' S.- Lat. 87" 39' W. ; 436 met. ; —0.2 C. 

 N° 3i9 b,s , Tangles II. Lat. 71° 14' S.- Long. 89 14' W. ; 460 met. ; +o.3 C. 

 On Errina gracilis Marenzeller, a species mentioned by Marenzeller from Tangles II 

 though not from 3ig. The Errina is said to hâve been growing on a Gasteropod. 



Micropora coreacea Esper. 



A few zoœcia on a stone are considered to belong to this species. 



Habitat. — N° 619, Tangles VIII. Lat. 70 00' S.- Long. So'^ 48' W.; 5oo ? met.; +0.9 C. 



