BY H. I. JENSEN. 845 



iii. PhysiocxRapiiy and Topography. 



(a) Undulating Sandy Cotmtry. — The coastal tract from which 

 the Glass House Mountains rise as isolated peaks, consists of gently- 

 undulating country, which appears a " plain " or '^flat " when 

 viewed from the sea. It is covered with a sandy soil sustaining 

 a forest vegetation consisting of Eucalypts (white-gum, blue-gura, 

 red-gum, stringy-bark, cabbage-trees, ironbark), Tea-trees, Banksia, 

 Casuarina, Callistemon and Xanthorrhcea. The grasses are poor. 

 In the sour-soiled, swampy flats the grass-tree (Xanthorrhcea) 

 never produces a trunk as on the ridges. Near the trachytic 

 peaks themselves the sand}^ soil gives place to a grey, ash-like 

 soil, which is even more incapable of supporting healthy vegeta- 

 tion, inasmuch as it becomes sour in wet seasons from want of 

 drainage, and cakes in dry weather. 



This kind of country ^extends from Deception Bay on the east 

 to the outcrop of the Palaeozoic rocks on the west. The Palaeozoic 

 rocks are met with about seven miles west of Caboolture; here 

 their junction line with the Mesozoic takes a north-westerly trend 

 so that they are only reached in fifteen or sixteen miles going due 

 west from the Glass House Mountains Station, which is fourteen 

 miles north of Caboolture, and about forty-six miles north of 

 Brisbane. The D'Aguilar Range, which forms the watershed 

 between the coastal streams and the Stanley River (a tributary 

 of the Brisbane River) basin, consists at Mt. Mee of Palaeozoic 

 rocks ; but from the vicinity of Delaney's Creek northwards it 

 becomes a mere sandstone ridge, whose constituent rocks are of 

 Mesozoic age. 



The Palaeozoic rocks of Mt. Mee and neighbourhood consist of 

 slates, schists, phyllites, granites and diorites with veins of quartz 

 intersecting the sedimentary rocks, and dykes of gneiss, syenite, 

 hornblende rock and gabbro intersecting the granites. Many of 

 the quartz veins and leaders, and several of the dykes are metal- 

 liferous. 



The sandy soil of the coastal tract overlies and is probably 



derived from the subaerial denudation of a formation consisting 



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