Zoologij.-] NATURAL HISTORY OF VICTORIA. [Pottjzoa. 



Plate 98, Figs. 1-5. 

 RETEPORA PHO^NICEA (Busk). 



Description. — Polyzoary expanded, foliaceous, convoluted ; fenestrce small, 

 rounded, or elliptical, narrower than the interspaces ; cells enlarged upwards, sepa- 

 rated by narrow, raised lines ; surface smooth or perforated by a few large foramina ; 

 mouth rounded, projecting* forwards, in youngest cells with a fringe of short spinous 

 processes or serratures and a sinus below, in older with an entire or slightly serrated 

 margin, and usually a minute rounded sinus on the lower lip ; operculum broad, 

 rounded, with the muscular impressions small, round, and at a distance from the 

 margin ; a broad avicularium with sharply triangular mandible below the mouth ; 

 ovicell rounded, sub-immersed, the lower part with a broad mesial plate curving 

 downwards and backwards -, posterior surface nearly smooth or sub-granular, with 

 numerous prominent vibices and a few minute avicularia. 



References. — Busk, Brit. Mus. Cat., Mar. Polyzoa ; Hincks, Ann. and Mag. 

 Nat. Hist., May 1878. 



Port Phillip Heads ; Portlaud, Mr. Maplestone ; King's Island, 

 Mr. McGowan. 



This species forms small, convoluted masses of a beautiful vivid 

 red colour. The finest specimen I have seen is that figured. The 

 cells, which are separated by narrow raised lines, are smooth or 

 sub-granular, and have usually several rounded foramina towards 

 the margins. These are commonly arranged in two pairs, one on 

 the upper part near the mouth, the other towards the base. In a 

 young specimen, ^tli of an inch in diameter, for which I am 

 indebted to Mr. Wilson, the cells have the mouth nearly circular 

 with a thick fringe of short processes, longest above, but not 

 developed into distinct spines, connected by an intermediate cal- 

 careous expansion. In old cells the peristome is smooth and little 

 prominent, or projects more and is ol)Scurely serrated ; there is also 

 usually, but not always, a small rounded sinus in the lower lip. 

 In most cells there is a large avicularimn below the mouth, Avitli 

 a broad, sharply triangular mandible directed upwards. The ovi- 

 cells are very conspicuous. They are white, sub-immersed, and at 

 the lower part have a broad mesial plate which curves downwards 

 and backwards, leaving a rounded notch on each side. Their 



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