JBRl'OZOA FROM S.W. VICTORIA, AUSTRALIA.. 



343 



65. Retepora rimata, sp. nov. Plate XVI. figs. 48, 53. 

 Zoarium probably reticulate ; branches slightly compressed. 



Zocecia cylindrical, convex ; surface smooth ; peristome much raised, 

 with a cleft in front the whole length of the peristome, expand- 

 ing at the base, the edges on the two sides of the cleft turned 

 inwards, peristome often surrounded in front with a raised rim. 

 Small subimmersed avicularia below the peristome, subtriangular 

 or suboval, pointing upwards, with a very minute opening near the 

 distal end. Dorsal surface divided by white raised lines, with small, 

 subcircular, acute avicularia and small bosses irregularly placed. 



This is common from Mount Gambier : but the state of fossi- 

 lization would not have permitted all the characters to be made 

 out if the " Yarra-Yarra " specimens had not served as a key. 



Loc. Fossil : Mt. Gambier (Lond. Geol. Soc. and Eth., jun., coll.). 



In one specimen the avicularia in the front are replaced by a simple 

 pore. This would unite the genus with Porinidae : and we here see 

 another example of the avicularia taking the position of pores, and 

 are led to regard avicularia as modified pores. 



66. Cellepora yarraensis, sp. nov. 



Zoarium cylindrical, dividing dichotomously, in one case throwing 

 out a branch forming an angle of about 80° ; diameter of stem 1-2 

 millim. Zocecia very irregularly arranged, placed sometimes very 

 crowded, sometimes far apart, indistinct ; peristome much raised on 

 the lower or avicularium side, usually not at all on the other, giving 

 it, when seen in profile, a triangular appearance ; at the proximal 

 part of the peristome an avicularium ; when this is broken down the 

 two large openings have the appearance so general in Celleporee ; 

 between the zocecia few large much raised perforated protuberances, 

 probably sometimes avicularian. Surface smooth, porcellaneous. 

 Oral aperture semicircular, rounded on the distal edge, straight on the 

 proximal, though when raised cells are seen the aperture appears 

 rounded. Aperture 0-08 millim. wide, Ol millim. long. 



I have an undescribed thin branching species of Cellepora from 

 Capri (near Naples) which also has the lower edge of the aperture 

 straight and in many respects resembles the present. 



67. Cellepora fossa, Hasw. Plate XVIII. fig. 89. 

 Sphceropora fossa, Haswell, " On some Polyzoa from the Queens- 

 land Coast," Proc. Linn. Soc. New S. Wales, vol. v. pt. i. 1880, p. 

 42, pi. iii. fig. 5, 6. 



Zoarium subglobular, flattened above, specimens 2-5 millim. in 

 diameter. On the upperside the zocecia are directed from the pole of 

 the zoarium ; on the underside they are directed towards it. Zocecia 

 subcylindrical or ovate or conical, very finely granular, erect (on 

 the upperside) : a few pores round the edge of the zocecium on the 

 upperside, but seldom on the back. Oral aperture rounded on the 

 distal wall, straight on the proximal. In the centre, immediately 

 below the proximal margin, a large, wide, erect, obtusely conical or 

 globular avicularium. Few large, spatulate, zocecial avicularia 



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