PLATE III. 



CTENOSTOMATA. 

 Alcyonidium, Elzerina, Victorella, Arachnidiitm, Arachnoidea. 



(Figs i and 10 were drawn vvith a Zeiss C Obj.; figs 2 — 9, ir, 14 and 15 with a Zeiss A Obj.; 

 and figs 12 and 13 with a Ross 2-inch Obj. All the figures were afterwards reduced '/.,. The scales, in /*, 

 are indicated at the foot of the Plate.) 



Fig. 1. Alcyonidium polyoum Hassall (p. 37). — Torres Straits (not 'Siboga'-Expedition). Six zooecia, 



growing on Euthyris obtecta, the zooecia of which are seen through the Alcyonidium. 

 Fig. 2. Elzerina blainvillii Lamx (p. 38). — Torres Straits (not 'Siboga'-Expedition). Distal end of a branch. 

 Arachnidium irregulare n. sp. (p. 48). — 376. B. 4 , Stat. 213. Zooecium. 



„ „ „ „ „ „ Two zooecia, the lower one with the 



kamptoderm everted. 

 „ „ „ „ „ „ Zooecium, with embryo in ovisac : 



basal view. 

 „ „ „ — 376. B. 2 , „ v Another zooecium, with polypide : 



basal view. 

 Arachnoidea protecta n. sp. (p. 50). — 378. E. 2 , Stat. 71. Zooecium with collar partially protruded. 

 „ n „ n „ „ Two zooecia in side view. Part of the 



collar, in its retracted position, is seen 

 in the right hand zooecium. 

 „ „ „ — „ „ „ Zooecium with its collar protruded. 



„ „ B „ „ „ Collar of the same specimen, more highly 



magnified. 

 „ „ „ „ „ „ Another zooecium, with short peristome. 



Victorella sibogae n. sp. (p. 45). — 451.B. 2 , Stat. 64. A group of old zooecia. 

 » v » v v A group of young zooecia. 



„ „ „ i) » » An old zooecium, with degenerated polypide; 



more highly magnified. 

 Fig. 15. „ „ „ „ „ „ An old zooecium, with functional polypide: 



magnification as in fig. 14. 



