16 Mr. A. W. Waters on Australian Bryozoa. 



pores round the border. The peristome raised at each side of 

 the aperture, but not at all on the distal end, where there is 

 one large jointed spine, occasionally replaced by two, nor is 

 the proximal edge raised. 



At one side, rather below the aperture, a large raised avicu- 

 larium with a round mandible, but sometimes replaced by a 

 gigantic avicularium almost the size of the zooecium. In one 

 specimen there is also one vicarious avicularium larger than a 

 zooecium, with a spatulate mandible. The operculum is thin, 

 scarcely chitinous, nearly orbicular, slightly curved inwards on 

 the lower edge, and quite plain. 



The ovicells are large, globular, much raised, and in 

 mature specimens there are two or three mucronate processes 

 and perforations on the front of the ovicell. 



In young ovicells the markings remind us of the trifoliate 

 stigma on the ovicells of a group of Retepora. 



Smiitia trispinosa, J., var. munita, Hincks. 

 (Pi. III. figs. 12, 13, 23.) 



Smittin trupimsa, Johnst. var., Ann. & Mag. Nat. Hist. ser. 5, vol. xiv. 

 p. 283, pi. ix. tig. 5. 



Specimens from Green Point have the zooecia heaped up 

 and short, with a peristomial sinus, caused by the peristome 

 being raised on both sides. The surface is coarsely granu- 

 lated, and to some zooecia there are three supraoral spines. 

 The ovicells are distinct, partly buried in the zooecia above, 

 with large pores over the surface, and there is usually an 

 elongate avicularium on each side of the aperture. The lyrula 

 and cardcllai are nearly equal and near together, and all three 

 are directed inwards ; but the operculum, on the other hand, 

 is turned upwards towards a kind of hood on the distal end of 

 the zooecium (see diagram, fig. 13). 



Loc. Port Phillip Heads (Victoria) ; Green Point. 



Smillia malleolus^ Hincks. (PL III. figs. 14, 15.) 



Porella 7nalleolus, Hincks, Ann. & Mag. Nat. Hist. ser. 5, vol. xiii. 

 p. 361, pi. xiii. fig. 5. 



In the specimen from Green Point the interoral avicularium 

 is very marked, with the mandible projecting far into the 

 aperture. The ovicells are wide and not very much raised. 



In the avicularium there is a calcareous process arising 

 from the calcareous bar. This I propose to call a ligula, and 

 have pointed out (" On the Use of the Avicularian Mandibles " 

 &c., Journ. Micro. Soc. ser. 2, vol. v. p. 776) that a ligula 



