BKYOZOA FROM ZANZIBAR. 521 



operculum. Myriozoum marionensis would seem to be Cellarinella 

 or related to it. Gephyrophora folymorpha has a large operculum 

 neai-ly round, with a wide vanna fitting into the poster, and the 

 muscular dot is some distance from the edge, in fact it is of a 

 Schizoporellidan character. 



It seems probable that E. occltisa must be made the type of a 

 new genus, and I expect that the examination of material suit- 

 able for cutting will result in a re-arrangement of classification 

 of the Myriozoidea of Levinsen, as the ovicells present such great 

 differences. I am loth to make new genera until we can see from 

 sufficient material what is to be grouped together ; at any rate, I 

 fail to see good reason for placing Escharoides occlusa * under 

 Myriozoum. 



Log. See Waters, "Red SeaBryozoa" p. 156. Wasin, Brit. 

 East Africa, 10 fath. (501) (520); Ras Osowamembe, Zanzibar 

 Channel, 10 fath. (504), collected by Crossland. 



HOLOPORELLA COLUMNARIS Busk. 



Cellepora columnaris Busk, Zool. Chall. Exp. vol. x. pt. xxx. 

 p. 194, pi. xxix. fig. 11, pi. xxxv. fig. 16 (1884); Waters, Ann. 

 Mag. Nat. Hist. ser. 6, vol. iv. pi. ii. figs. 1-6 (1889) ; Ortmann, 

 "Die Japanische Bryozoenfauna," Arcliiv f. Naturgesch. vol. i. 

 p. 55 (1890). 



Cellepora ciclaris MacG. Prod. Zool. Vict. dec. xvii. p. 243, 

 pi. 165. fig. 4 (1888) ; Thornely, "Ceylon Pearl-Oyster Fisheries," 

 vol. iv. Poly. p. 126 (1905); Records of Indian Museum, p. 195 

 (1907). 



The oral aperture has a denticle at each side. As shown in my 

 paper mentioned above, the columns are often very thick, ex- 

 tending through several layers of the zoarium. A specimen 

 of Holo'porella in my possession, named in manuscript celosia by 

 Busk, has similar columns passing through several rows of zooecia, 

 and the avicularian mandible has a double columella, while the 

 shape of the operculum also shows that it is a distinct species. 

 This is not, however, the species so named in the Busk collection 

 in the British Museum, where there are two other species named 

 celosia, MSS. 



I have had the opportunity of comparing Busk's types and 

 MacGillivray's co-types (?'. e., duplicates) in the British Museum, 

 and there can be no doubt as to the identity of columnaris and 

 ciclaris. 



In a specimen of columnaris from Wasin there are numerous 

 small hydroids extending far into the zoarium within, protecting 

 internal walls, formed by the Holoporella, prolonged slightly 



* Hincks considered Escharoides, a name given by Milne-Edwards for a subgenus 

 of Cellepora, as being now the genus of Sniitt, who used it for species with an 

 avicularium in the lip on one or both sides, but Smitt never fully diagnosed it. As 

 Escharoides, a name originally meaningless, has been used in a quite different sense 

 from Levinsen's, it would be much better if he recalled his genus Feristomella and 

 used it instead of Escharoides. 



