BY W. H. CLEMES, B.A., B.&C. 37 



bedded in the granite, showing conclusively that they 

 belong to an earlier age, but to what age is a matter for 

 future investigation. Permo-Carboniferous limestones are 

 resting unconformably above them, and, on the far side, 

 come down below sea-level, the granites having finally 

 disappeared. Thev continue round the corner of Cocks- 

 comb Head and form a huge semi-circle of cliffs extending 

 almost to Cape Boull anger and the He du Nord, which 

 are of diabase. These cliifs are the finest example of the 

 Lower Marine beds that we have in Tasmania. They are 

 regular and almost horizontal, though one or two examples 

 of lenticular deposition ai'e apparent. There are no strik- 

 ing examples of faulting or deformation siuch as appear at 

 Eagiehawk Neck and other localities. The cliffs slop© 

 down gradually to the west from a height of about 1,000 

 feet, with flat ledges underneath almost buried in a huge 

 talus of fallen blocks, some of which weigh many tons. 

 These rocks and the cliffs around them are studded with 

 fossils, brought into relief by weathering, and are simply 

 one solid compact mass of shell-remains, among which the 

 Eurydesmas with their thick globose forms predominate. 

 "Blocks of 40 and 50 tons v/eight seem to be simply made 

 up of a compacted conglomerate of this geniis"' (R. M. 

 Johnston). The basal beds are the usual gritty muctstones 

 more highl}^ studded than usual with ice-borne detrltusi; 

 some of the granite blocks embedded in the mud of this 

 old sea-floor must weigh many tons. Their angular nature 

 shows that they have been transported by ice-action, as 

 that is the only agency which could have carried them 

 for such a distance and preserved their shape intact. The 

 way in which the surrounding mud has been pressed up 

 around their edges also proves that they have been drop- 

 ped from melting floes and sunk to their present resting 

 place. 



Three zones are represented : — ■ 



1. Eurydesma Zone. 



2. Fenestella Zone.- 



3. Crinoiclal Zone. 



The first two zones have been well described by the 

 late E,. M. Johnston in his Geology of Tasmania and so 

 I need not elaborate on them here. 



The principal families represented in the first zone 

 are Spirifers, Pacliydoinus, Eurydesma, Notomya, 

 Aviculo'pecten, Stenopora, and Favosites. In the second the 

 .F enest\dlas and Protoretepora are interspersed with 

 Spirifers, Productus, Strophalosia, etc. The Crinoidal 

 Zone is composed almost entirely of a compacted mass of 



