Zoology.'] NATURAL HISTORY OF VICTORIA. \_Polyzoa. 



Description. — Zoarium crustaceous. Zooecia closely adjunct or slightly 

 separated and connected by an intervening- hasis, rounded or ovate ; front occupied 

 by 6-10 ribs on each side radiating from a smooth or ridged central spot or line, the 

 intervening sulci jiiercod by a row of small round foramina; a triangular smooth 

 space below the mouth usually bounded by a raised margin and with a small per- 

 foration at the lower part; mouth semicircular, with 4-0 spines on the upper 

 margin and frequently a thin setiform spine on each side below the angle. Ofccia 

 globular, smooth, with a vertical ridge or umbo. 



Referencb. — C. rndinla (including vnnominata), Hincks, Brit. Marine Polyzoa, 

 p. 185, pi. xxxvi., figs. 1-9. 



Port Pliillip Heads, on shells and calcareous nodules. 



This beautiful species is suliject to considerable variation. The 

 zoa'cia are usually ovate or nearly round, sometimes they are 

 narrower and ])roduced below, or they may be very broad. The 

 centre is usually raised into a ridge or keel, terminating above 

 in an unil)o ; sometimes, however, it is smooth. The aperture in 

 the triangular smooth space below the mouth is by no meang 

 constant and the bounding ridge is frequently absent, as are also 

 the setiform spines. The extent and prominence of the ooecial 

 ridge varies. Avicularia are rarely (in Australian specimens) 

 developed between the zoa?cia. 



There is no doubt that Mr. Hincks is right in uniting C. radiata 

 and innominata. 



Explanation of Figures. 

 Plate 187. — Fig. 3, small group of zouniii, with (lie ribs very prominont and showing the 

 setiform .spines. Fig. 4, three zoteeia, from another s])ccimcn, sliglitly separated from eiich 

 other. 



Plate 187, Fig. 5. 

 CRIBMLTNA SETIROSTRIS (McG.). 



Description. — Zoarium crustaceous. Zooocia distinct, elongated, surface with 

 numerous round or ])yriform ibraminii, frequently arranged in irregular single or 

 double transverse rows; mouth arched above, straight below, margin thickened and 



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