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 zocecium. In one 
specimen there is also one vicarious avicularium larger than a 
zocecium, 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. 
Smittia trispinosa, J., var. munita, Hincks. 
(Pl. IIT. figs. 12, 13, 23.) 
Smittia trispinosa, Johust. var., Ann. & Mag. Nat. Hist. ser. 5, vol. xiv. 
p. 283, pl. ix. fig. 5. 
Specimens from Green Point have the zocecia 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 zocecia there are three supraoral spines. 
The ovicells are distinct, partly buried in the zocecia above, 
with large pores over the surface, and there is usually an 
elongate avicularium on each side of the aperture. The lyrula 
and cardelle 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 zocecium (see diagram, fig. 13). 
Loc. Port Phillip Heads (Victoria) ; Green Point. 
Smittia malleolus, Hincks. (Pl. III. figs. 14, 15.) 
Porella malleolus, Hincks, Ann. & Mag. Nat. Hist. ser. 5, vol. xiii. 
p- 361, pl. 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 
