or Little Known, Polyzoa. 103 



mouth in young specimens nearly round with a projecting 

 mucro below ; in old specimens contracted downwards, and 

 usually with a squared denticle in the lower lip, which is 

 also slightly thickened; below the mouth is a small elliptical 

 avicularium on the upper part of a bullate projection ; ovicell 

 small, globular, smooth, with faint radiating lines. 



Common. 



As already stated, this species was originally described 

 from bad specimens, and I have, therefore, given a more 

 correct figure and an amended description. Hincks had 

 already (Annals & Mag. Nat. His., 1881) given a figure, and 

 noticed the oral denticle (which is frequently absent) and 

 suboral avicularium. 



Cellepora exigua, M C G. Fig. 7. 



The figures represent a common form which I described 

 in 1860. I now think that it is probably identical with the 

 very variable Rkynchopora bispinosa, and shall, in a future 

 communication, give additional figures and a full descrip- 

 tion. 



Rkynchopora profunda, n. sp. Fig. 8. 



Polyzoary encrusting; marginal cells oval, smooth or 

 areolated at the edges ; in the youngest the mouth arched 

 above, slightly hollowed below ; when a little older one side 

 becomes enlarged, and from it projects an unciform process, 

 the point of which is turned slightly upwards ; as growth 

 advances a calcareous deposit, at first arranged in a 

 reticulate manner on the margins of the cells, increases in 

 bulk until the original cell is much thickened, and the 

 mouth is buried at the bottom of a deep cavernous opening ; 

 in these cells the upper lip is sometimes minutely crenulate ; 

 the uncinate process is always plainly seen deep down, and 

 has an avicularium in the front with a broadly triangular 

 mandible opening forward ; the surface of the raised 

 calcareous parts is irregularly nodulated, and there are a 

 good many large avicularia with more or less spatulate 

 mandibles scattered over it. 



Port Phillip Heads; Mr. J. B. Wilson. 



I refer this species doubtfully to Hi nek's genus Rkyn- 

 copora. The characteristics are the triangular mandible of 

 the avicularium on the uncinate process opening directly 

 forward, and the extraordinary calcareous growth which 



P 



