678 P. MARTIN DUNCAN ON SOME TASMANIAN FOSSIL CORALS. 



developed, and marked with faint transverse ridges and furrows ; it is 

 attached or replaces the wall, and there are no costae. The septa 

 are in five cycles in six systems. The columella is small in area, but 

 is well developed and papillose. The dissepiments are distant. 



Diameter of calice \ inch. 



Locality. Table Cape, Tasmania. 



The glazed epitheca, the absence of costae, and the high septal 

 number distinguish this species from all others. In its habit of 

 growth it resembles Dendrojohyllia cornigera of the Mediterranean 

 and North Atlantic ; but it only has slight generic affinities with D. 

 aocifuga of Port Essington in the Australian seas. 



The new species has no close allies in any of the Australian Ter- 

 tiary deposits, and it will serve to characterize the particular beds 

 whence it was taken. It was found associated with large specimens 

 of Placotrochus deltoideus (Dune), a well-marked coral, which is cha- 

 racteristic of a definite geological horizon in Yictoria, South Australia. 

 This fine Placotrochus was found over a great area in the Murray 

 Tertiaries, in those of Hamilton, and in the lower (no. 9) beds of the 

 Cape-Otway section*. 



These strata are low down in the lowest superficial fossiliferous 

 deposits of the south-eastern part of the Australian area, and rest 

 either on Silurian rocks or on Tamiopteris sandstones. They are 

 covered normally by a dense basalt, which is overlain by later fossi- 

 liferous deposits — those of the Gambier series ; and these are covered 

 here and there by volcanic ejectamenta. The upper deposits are 

 deep-water ones, and contain Polyzoa in abundance ; but the loWer 

 series, the Lower Cainozoic, collected in moderately deep water and 

 in shallow water. 



As Northern Tasmania is close to the Tertiary deposits of Victoria, 

 and as both contain the same well-marked coral, which has a very 

 definite vertical range in the last-named district, it is reasonable to 

 correlate the Table-Cape deposits with the new Dendro'pliyllia with 

 the Lower Cainozoics of the mainland. 



One specimen of a compound or reef-building coral was found in 

 the Tasmanian deposits. It is part of an incrusting and short 

 Heliastrsean. The calices are so worn that they cannot be distin- 

 guished ; but the septa and dissepiments are preserved. No such 

 corals were found in the Australian deposits. 



EXPLANATION OF PLATE XXXVIII. c. 



Fig. 1. Specimen of Dendrophyllia epithecata. Nat. size. 

 2. Half the calice. Twice nat. size. 



* P. M. Duncan, Quart. Journ. Geol. Soc. vol. xxvi. p. 284 ; Wilkinson and 

 Daintree, Geol. Survey of Victoria. 



