66 GEOLOGY OF TASMANIA. 



Gangamo'pteris, Sfirifera tasmaniensis, S. darwinii, S. duo- 

 decimcostata, Terehratula saccidus, Avicida, Area, Aviculo- 

 pecten, Eurydesma sacculus, Edmondia, Inoceramus, Pachy- 

 domus pusillvs, Pleurotpmaria inorrisimia, Conidaria, Theca, 

 &c. 



On the north bank of the Henty River, on the West 

 Coast, between the Henty and Badger, the lower coal 

 measures are hard dark grey shales, which contain Gangam- 

 opteris spatulata (McCoy), G. ohliqua (McCoy), Noeggera- 

 thiopsis media (Ettingsh.). Above these are mudstones 

 and impure limestones, with Fenestella plebeia, F. internata, 

 Protnretepora ainpla, Stenopura tasmaniensis. 



In the North-East part of the!\ Island, foraminiferal lime- 

 stone of this system has been found by Mr. Thos. Stephens. 

 At Harelield, in the Fingal Basin, a diamond-drill bore has 

 revealed the existence of 97 feet of conglomerates, sandstone, 

 and shales, resting on Silurian slates, at a depth of 674 feet 

 in the bore-hole. These underlie the Upper Marine beds. 

 Very little coal was found, but the shales contained im- 

 prints doubtfully referred to Schizoneura and Gangamop- 

 teris. The Upper Marine beds overlying these were 313 

 feet thick, and consisted of fossiliferous blue shale, lime- 

 stones, mudstones, &c. 



At Mount Cygnet, the low^er coal measures rest on the 

 fenestella beds, and are overlaid by 200 feet of grey sand- 

 stone. The coal shales contain impressions of Vertehraria 

 australis and Gangamopteris spatulata. 



At Adventure Bay, on Bruni Island, lower coal measure 

 shales and seams lie conformably on the lower marine mud- 

 stones, conglomerates, and sandstones. They contain 

 dwarfed forms of Gangamopteris spatvlata, G. ohliqua, Gloss- 

 opt eris hrowniana, var. prcecursor (Brongt.). 



At Southport, brown sandstone is overlaid by carbon- 

 aceous shales, with imprints of Vertehraria australis. The 

 Adventure Bay and Southport series form the uppermost 

 beds of the system. 



The elseolitic and trachytic rocks, which are developed at 

 Port Cygnet and Oyster Cove, are referred provisionally to 

 the close of this period. Some of them appear to be fluidal, 

 and interbedded with the Permo-Carboniferous mudstones 

 and sandstones, but further examination is requisite. The 

 majority are intrusive rocks, forming parts of a mass of 

 elseolite-and alkali-syenite, M^th associated dykes of phono- 

 litic, tinguaitic, and trachytic porphyries. The accessory 

 minerals of the nepheline rocks, nosean, aegirine, sodalite, 

 melanite, &c., are present here in all the wonderful variety 

 characteristic of that group. Mounts Livingstone and 



