108 A MONOGRAPH OP THE TERTIARY POLYZOA OP VICTORIA. 



S.P. ; M.C.; B. ; C.B. Living. Australia. 



The specimens are not in a very good condition, and only a few of the zocecia 

 shew the marks of the oral spines. The one shewn in fig. 5 I was at first inclined to 

 refer to a different sjDecies, hut I think it is only an early stage. In some of its 

 zooecia there is a row of 6-8 sjnnes on the upper edge of the thyrostome. In most 

 there is no appearance of the internal denticles, but in one they are present. 



Var. nummularia, Busk. PL XIV., figs. 6, 6a, 6b, 6c, Tenison Woods, 

 T.B.S.V., 1861, p. 3 ; C. tridenticulata, Waters, Q.J.G.S., 1885, p. 306. 



In this variety the zoarium is discoid or dome-shaped, 10-20 millimetres in 

 diameter, and is formed of several superposed layers of zooecia. The overlapping of 

 these is marked on the under surface by concentric rings, the zooecia themselves 

 being distinct and arranged in regular radiating series. In some of the largest 

 specimens the posterior surface is very concave, and the zoarium has the app earance 

 of that of a large Lunulites. In others, mostly smaller, the posterior surface is 

 convex, the whole zoarium being proportionately thicker and dome-shaped. 



S.P; B.B, ; C.B. ; G. 



3. C. fossa, Haswell, sp. PL XIV., figs. S, 9, 10. 



Sphcerophora fossa, Haswell, Proc. Linn. Soc. N.S.W., Vol. V., 12 ; Cellepora 

 fossa, Waters, Q.J.G.S., 1881, p. 313; 1885, 307. 



Zoarium small, about five millimeters diameter, lenticular, more convex on one 

 side ; in most specimens, on one side, one or more small deep round pits. Zooecia 

 confused, projecting forwards, rounded; thyrostome arched above, straight and 

 entire below; a rounded avicularium on an elevation immediately below the 

 thyrostome. 



S.P. ; B.R.; C.B. ; W.P. ; C.C. (W.). 



In most specimens there is a single pit on one side near the centre, in others 

 there are several, and occasionally they are absent. The suboral elevation is mostly 

 broken open, when it forms with the thyrostome a single large aperture divided by 

 a narrow cross-bar. In one specimen it is in most of the zooecia produced into a 

 slightly elevated conical process with a small opening, evidently avicularian, at 

 the summit. 



-1. C. serrata, n.sp. PL XIV., fig. 7. 



Zoarium circular, convex above, flat or hollowed below, with a central pit on 

 the under surface. Zooecia irregularly arranged, rounded, surface granular ; 

 thyrostome arched above, contracted below ; lower lip straight, with about six short, 



