Zoology.] NATURAL HISTORY OF VICTORIA. \JPolyzoa. 



Description. — Cells widely ovate. Fenestrae 5. Lower lip with a minute 

 rounded notch. ' Lateral processes large; avicularium large, supporting a widely- 

 open cup-shaped process above. Back of cell finely sulcated. 



Eeference. — Busk, Voy. Ratt., i., 356 ; Cat. Mar. Pol. Brit. Mus., t. 6, f. 

 1, 2, 3. 



Forms dense tufts, 2 to 4 or 5 inches high, of a reddish -brown 

 color ; common on the Victorian coasts. 



This species is readily distinguished by the number of the 

 fenestras, the slight notch in the lower lip, the form of the lateral 

 processes, with the widely-open, superior, cup-shaped, chamber, and 

 the sulci on the back of the cells. 



Explanation of Figures. 



Plate 24. — Fig. 1, natural size. Fig. la, front view of a branchlet, magnified. Fig. \h, 

 back view of ovicell, magnified. Fig. lc, front view of ovicell, magnified. Fig. \d, back view 

 of a branchlet, magnified. 



The species of this genus may be divided into five well-defined 

 groups. The first, Fenestrates* of Busk, is distinguished by the 

 presence of a certain number of marks or fenestra? on the front of 

 the cell, caused by the deficiency of the ectoderm at these points. 

 The species are mostly of large size, and the ovicells are large and 

 terminal. In the second group, Vittateef of Busk, there are no 

 fenestra?, but there is a narrow lateral or sublateral band or vitta 

 on each side. The ovicells are of two forms, either on the summit 

 of a cell of a series and cemented to the succeeding one, which is 

 sessile, so that the three form a continuous mass ; or they are 

 terminal, and situated on the summit of a cell of a geminate pair. 

 They are usually small species. The third group, Simplices of 

 Busk, comprising the single species C. carinata, has neither fenestra?, 

 vitta?, nor any other appendage, except the peculiar transversely 

 spreading lateral processes. The fourth group, Auritce\ of Wyville 

 Thomson, has neither true fenestra? nor vitta?, and is distinguished 

 oy the presence of several thick blunt hollow processes on the 

 upper edge of the mouth. The fifth group, Fasciatee of Thomson, 

 consists of the single species C. Harveyi. 



* Fenestrate includes C. margaritacea, plagiostoma, ventricosa, hastata, rufa, cribraria, alata, 

 lorica, intermedia. 



f Vittata includes C. formosa, elegans, perforata, Buskii, Hannafordi, crystallina, cornuta. 

 % Aurita includes C. aurita, geminata. 



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