Zoology."] NATUKAL HISTORY OF VICTORIA. [Polyzoa 



Plate 24, Fig. 16. 



CATENICELLA AURITA (Busk). 



Description. — Cells ovate or sub-globular. Front tuberculate, the larger 

 tubercles towards tbe centre. Lower lip deeply notched. On each side of the 

 mouth above are two or three thick, hollow, blunt processes, the upper the larger. 

 Lateral processes large, with gaping avicularia. 



Reference. — Busk, Cat. Mar. Pol. Brit. Mus., t. 4, f. 1, 2, 3. 



Occurs in small whitish tufts, about half an inch or an inch 

 high, attached to zoophytes and algae. 



In this species the appearance of the cell varies very much, ac- 

 cording to the age and state of preservation of the specimen. In 

 good specimens the front is richly tuberculate, and there are no 

 perforations, or at most one suboral. With age or attrition the 

 lateral tubercles disappear and the central larger ones are opened. 

 In old specimens, as commonly seen, we have the appearance of 4 

 or 5 fenestra surrounding a large, raised, suboral opening, as figured 

 and described by Busk. The ovicell is situated on the summit of 

 a single cell, and has a gaping avicularium on either side. The 

 avicularium is generally much smaller or abortive on one side. 



Explanation of Figures. 



Plate 24. — Fig. 16, natural size. Fig. 16a, front view of a branchlet of single and double 

 cells, magnified. Fig. 166, front view of two cells, one with ovicell, magnified. Fig. 16c, back 

 view of single and double cells, magnified. 



Plate 24, Fig. 17. 



CATENICELLA GEMINATA (Wyv. Thomson). 



Description. — Axial cells g-eminate. Front tuberculate. Mouth surrounded 

 above by seveml (4 or 5) blunt hollow processes. Lower lip deeply notched. From 

 one cell of each geminate pair, except at a bifurcation, springs a single terminal 

 wedge-shaped cell, surmounted by two hollow blunt processes. 



Reference. — Wyville Thomson, Dublin Natural History Review, April 1858. 



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