596 Canon A. M. Norman — Notes on ilie 



Goecia are not prominently raised and are also smaller in 

 size than in this species. 



Genus Ellisina*. 



Type, EUisina {Memhrmiipora) leimta, Hincks. 



Differs from Oochilina in not having avicularia occupying 

 separate cells between the zooecia : but, instead, furnished 

 •with avicularia, ovoid or triangular, situated on the hinder 

 portion of the zooecium. The ooecium is well developed, 

 typically with a flattened area on its front. In the type 

 species the pore-chambers are very large (PI. XIII. fig. 4) : 

 one distal; the position of the remaining chambers is very 

 unusual, the two front lateral pairs project outside the side 

 walls ; and the two posterior pairs are seen inside the side 

 walls, which is the reverse of the usual rule. 



Membranipora albida, coronata, and minuscula of Hincks, 

 and M, incrustans, Waters, would seem to belong to this 

 genus. 



Genus Alderina t^ gen. nov. 



Front wall entirely membranous, side walls usually 

 crenulated ; no lateral spines. No avicularia (but nodulous 

 processes sometimes developed in different positions on the 

 side of the zooecium). Ooecium usually bearing (either a 

 rib or) a depressed area in front. Pore-chambers in the type, 

 two pair of lateral and two distinctly marked and separated 

 distal (well figured by Levinson, Zool. Dan,, Mosdyr, 1894, 

 pi. iv. fig. 27). As in EUisina, the two front pairs of pore- 

 chambers usually extend outside the lateral walls, and the 

 tAvo posterior inside. 



Type, Alderina [Membranipora) inibeUis, Hincks. 



I provisionally place M. solidida in this genus, but it 

 differs considerably from the type. The parts of the generic 

 description which are in brackets apply to it, and not to 

 A. imbellis. 



PI. XIII. fig. 8 represents the front portion of a young 

 zooecium at the edge of the zoarium of A. solidida. 



Genus Amphiblestrum, Gray. 



Type, Amphiblestrum Flemingii, Busk |. (PL XIII. fig. 5.) 



Hinder portion of the area covered with a calcareous 



* After John Ellis, the old cand excellent author on '' Corallines." 

 t Named after that excellent naturalist, J. Alder, the dearly loved friend 

 of bygone years. 



X See Busk, Eeport ' Challenger ' Exped., Polyzoa. 1884. p. G5. 



