5dC) Canon A. M. Norman— iV^o^es on the 



ooecia are not prominently raised and are also smaller in 

 size than in this species. 



Genus Ellisina*. 



Type, EUisina {MembrnmjJora) levata, Hincks. 



Differs from Ooch'ilina in not having avicnlaria occupyins; 

 separate cells between the zoa'cia ; but, instead, furnished 

 with avicularia, ovoid or triangular, situated on the hinder 

 portion of the zooecium. The ooecinm 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 tlie side 

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

 walls, which is the reverse of the usual rule. 



Meinbranipora alljida, coronata, and minusciiln of Hincks, 

 and M. incnista7is, Waters, would seem to belong to this 

 genus. 



Genus Aldehina f, gen. nov. 



Front w^all entirely membranous, side walls usually 

 crenulatcd ; no lateral spines. No avicularia (but nodulous 

 processes souieLimcs developed in different positions on the 

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

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

 two pair of lateral and two distinctly marked and separated 

 distal (well figured by Levinson, Zool. Dan., Mosdyr, l89-f, 

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

 chambers usually extend outside the lateral walls, and the 

 two posterior inside. 



Type, Alderina [Mernbranipora] imbelUs, Hincks. 



I provisionally place M. solidula 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. imbelHs. 



PI. XIII. fig. 8 represents the front poi'tion of a young 

 zouccium at the edge of the zoarium of A. solidula. 



Genus Amphiblestkum, Gray. 

 Type, Amphiblestrum FlcDiiiigli, Busk \. (PI. XIII. fig. 5.) 

 Hinder portion of the area covered with a calcareous 



* After John Ellis, the old uiid e.xct'llent author on '' Corallines." 

 t Named after that excellent natiiraiist, J. Alder, the dearly luved friend 

 of bygone years. 



J ".See f>u.';k, Report * Challeiii;-er ' I'].\ped., Polyzoa, fS84, p. Go. 



