44 EXPÉDITION ANTARCTIQUE BELGE 



Habitat. — Exp. Antarct. Belge. 



N° s 570, 5g6, Tangles VII. Lat. 70 23' S.- Long. 82°47' W. ; 480 met. ; +0.8 C. 



N° 619, Tangles VIII. Lat. 70 00' S.- Long. 8o°48' W. ; 5oo ? met. ; +0.9 C. 



Microporella exigua sp. nov. 



PI. III. figs. 3rr. h 



Zoarium adnate (on stones). Zoœcia oval, ventricose, porcellanous, smooth ; the médian 

 pore is round and situated about the middle of the zoœcium on a slight élévation; the pores 

 on the surface are round and do not show any signs of stellate structure, being less numerous 

 near the border than in M. parvipora nov. ; further there are usually two pores immediatelv 

 below the aperture ; on the distal border of the aperture there are eight spines. The oral 

 aperture is relatively longer than in other Microporella'. There is one distal pore chamber, 

 and apparently three latéral ones. The ovicell is unknown. This species is smaller than 

 either M. Malusii Aud. or M. parvipora nov., but is closely allied to the later. 



Habitat. — Exp. Antarct. Belge. 



N° 570, Tangles VII. Lat. 70 23' S.- Long. 82 (.7' W. ; 480 met.; +0.8 C, one 

 spécimen. 



N° s 619, 683, Tangles VIII. Lat. 70°oo / S.- Long. 80048 W. ; 5oo met.; +0.9 C. ; 

 only a few zoœcia. 



Microporella proxima sp. nov. 



pi. u. fig. 16) 



Zoarium incrusting. Zoœcia smooth, porcellanous, with small round pores, not stellate, 

 situated near the border and at the distal end ; also a small round médian pore near to the 

 oral aperture, and sometimes an umbo below. There are six oral spines at the distal border 

 of the semicircular aperture, and on a colony from 070 there is an ovicell which is globular, 

 raised, smooth, with a row of small pores near to the base. Frequently the zoœcia are not 

 in contact, and then the interspaces are rllled up by an irregular growth with moderate sized 

 pores in the calcareous wall. 



This and M. exigua nov. are closely allied, in some respects resembling the northern 

 M . impressa Aud. from which however thev are quite distinct. Both Hixcks and I hâve made 

 a mistake in considering the M . impressa Aud. and M. bimucronata Moll. ('), as varieties. They 

 both occur in the Mediterranean and off the British coasts, and they can be distinguished 

 by the pores, for M. impressa has a small round médian pore, and the suriace pores are also 

 round and plain, whereas in .1/. bimucronata the médian pore has a cruciform opening and 

 the surface pores are stellate. A most interesting fact, of greater importance is, that the central 

 zoœcium, namelv the primary, has in neither species a médian pore but instead there is a 

 sinus in the aperture, and in .1/. impressa the operculum of the primary is as seen in spécimens 



(1) See my figure. (Ami. Mag. Nat. Hist., ser. 5, vol. III, pi. VIII, figs. 2. 3.) 



