93 



ill a spherical, transparent body near llie lip of the basal side of the ascending 

 part of the zoa-ciuni in a large numi)er of specimens of Acted angiiina, and con- 

 siders this to be an ooecium. The great transparency of this little globe, which 

 has enal)le(i Waters to count the cell-divisions of the egg, seems to indicate, 

 tlial it is not calcareous, and this fact in connection with its for an oa'cium, 

 very unusual position on the l)asal side of the zoa'cium, speaks decidedly against 

 the ocecial nature of these globes. I must therefore regard the supjiosed ovicellular 

 wall only as a shell membrane surrounding the egg. 



Smitt' has already called attention to Ihe great agreement between the members 

 of this family and the Ctenostoiiuitd; but when he specially compares Acted with 

 the family Vesiciilariidae, we must remark, that this genus shows a much greater 

 agreement with the families Ciitindroeciiddc and Victoretlidae, in which the zooecium 

 according to Hincks also consists of an adherent and an ascending j)orlion, while 

 they have no real stolon. In all Ctenostome families, where the zorecia issue from 

 a stem or stolon consisting of kenozooecia, the zooecia die away and can be 

 renewed, whilst such a renewal does not take place where there is no stolon, 

 as in the two above-mentioned families, and according to this, the peduncles in 

 Tvitkelln must belong to the stolon and not to the individual zooecia. Smitt' 

 has also called attention to the fact that Acted, in the cylindrical form of the 

 zooecia and the rich development of pores, shows agreement with the Cijclostomatd, 

 and he imagines the possibility that the latter may have had a Ctenostome origin. 

 Without entering further into this question I wish only to point out in this 

 connection that in the Cyclostome species Stomatopord <idltkd d'Orb. - the zooe- 

 cium, as in Aetnu consists of a decumbent and an ascending part. On the other 

 hand, the agreement which an Acted shows with such a species as ■Mncroncl!a< 

 cotlmnnca Kirk, is of (juite a superficial nature, as the ascending tube-shaped 

 portion in the last-mentioned species is only a periston! and cannot therefore be 

 compared with the ascending portion in an Acted, which has an operculum 

 near the tip. 



Family Bicellariidae. 



Kncnitiiddc Hincks, Notainiidae Hincks. 

 (Pis. III-V). 



The zod'cid as a rule slightly calcified and in most cases with a large mem- 

 branous frontal area. Where a distal wall is developed (wanting in Hcduia and 

 Stnlonclla) it is nmre or less ascending and its basal edge is then placed more or 



' 99 a, p. 46U. " 8(5, VI. 7.59, ligs. 1—3. 



