president's address. 597 



but in the absence of a description of the varieties of Lejndoden- 

 dro7i met with in West Australia, this cannot be considered an 

 established fact. It is certain, however, that at the close of the 

 Carboniferous Period in Australia the Main Dividing Range of 

 Eastern Australia occupied approximately its present position, 

 and in places, as near Mount Lambie, the land probably stood far 

 higher than it does now, as proved by the great anticlinal curves, 

 now deeply denuded, though still in places between 3000 and 

 4000 feet above sea-level. In Tasmania Carboniferous deposits 

 and Lepidodendron are wholly wanting as far as known at present, 

 but it must be remembered that much of that island, especially 

 the western area, has not yet been geologically examined in detail. 

 There is no proof at present that this Lepidodendron Flora ever 

 reached either Tasmania or New Zealand. 



General Summary. 



The observations recorded in the above paper, if correct, and 

 I have done my best to try and arrive at the truth, may warrant 

 the following conclusions : — In Pre-Cambrian (Archaean) time 

 strata were deposited remains of which have been preserved, (1) 

 in Tasmania, (2) near Adelaide, (3) in the Mount Macdonnell 

 Ranges, (4) in the Kimberley District of Western Australia, and 

 (5) perhaps in the Southern Island of New Zealand. The best 

 evidence for the Pre-Cambrian age of this group has been 

 obtained in Yorke's Peninsula, near Adelaide, where the 

 Archaean rocks are strongly unconformable to the Olenellus- 

 Salterella zone of the Lower Cambrian Series. 



The beds of limestone and dolomite at the Macdonnell Ranges 

 in South Australia, interstratified with the Archaean rocks, and 

 the graphite and contemporaneous C?) ironstone are strongly 

 suggestive of contemporaneous life in Pre-Cambrian times in 

 the Australasian region, and the high differentiation of animal 

 life in the succeeding Lower Cambrian rocks points to the 

 same conclusion. Before the Lower Cambrian rocks were 

 deposited in Yorke's Peninsula and the Mount Macdonnell 



