BY H. I. JENSEN. 847 



In the sandy countiy, swampy tracts are abunrlant. East of 

 the D'Aguilar Range they seem to mark the position of old water- 

 courses. The Lagoon Creek marks the position of an old water- 

 course, the greater part of whose drainage area has now been 

 captured by the Caboolture River. The swamps contain deep 

 black, peaty soil, consisting of matted vegetable matter, logs, etc., 

 beneath which there is a floor of sandstone, sand and gravel, or 

 clay. The lagoons or ponds in the swamps quite commonly have 

 sandstone floors and walls, this sandstone containing petrified 

 wood similar to and as abundant as that obtained in the rocks 

 of the D'Aguilar Range. 



Along the Deception Bay Coast we meet with numerous shell 

 banks, containing oyster shells, Pecten, Cerithium, Area antiquata 

 and other shells, some of these banks being over a mile from the 

 shore. These may indicate that some elevation has taken place, 

 but it is perhaps more likely that they mark the old shore-line, 

 land-resumption slowly taking place through tidal action. How- 

 ever there are grounds for believing that some elevation has taken 

 place in recent times, some of the hills fronting the N.W. corner 

 of Deception Bay having the appearance of true raised beaches. 

 The sand banks more than two miles from the shore-line are 

 certainly of wind-blown origin, containing no marine remains. 

 These banks are, in my opinion, not river drift, the sand grains 

 being too tine and even-sized to have a fluviatile origin. 



Land -resumption by the action of the sea and organised life 

 combined is at present going on in Moreton Bay ; the coastal 

 alluvium may, therefore, consist of old shore-banks rendered terra 

 firma by the gradual recession of the sea, and man}^ of the salt 

 marshes along the coast may represent little inlets and mouths of 

 creeks, resumed in this way. (See Part vi., Notes by H. L. 

 Kesteven). 



(6) The Glass House Mountains. — These mountains are situated 

 on an elliptical area, having its long axis north and south. The 

 centre of the area is about 44 miles N. of Brisbane. They all 

 rise very sharpl}^ out of the Coal Measure sandstone, their summits 

 being either quite bare or only scantily decorated with a few 



