102 SECTION AT ONE TREE POINT, 



R.S. TAS. 



moraine, many of the present difficulties would disappear. 

 One of the- chief arguments against the moraine hypothesis 

 is the present position of the leaf bed series, but were the 

 view that the leaf bed series rest in a trough fault, that 

 is to say, are now in a lower position than they were 

 originally, correct, one of the chief objections against the 

 glacial origin of the Breccia would disappear. 



B. The Leaf Beds. 



The leaf beds represent a series of finely laminated 

 clay of whitish colour, which towards its base on the 

 southern section becomes somewhat arenaceous. When 

 exposed to the air the leaf beds soon crumble away, and 

 this unfortunately renders the presei'\'ation of the fossil 

 remains most difficult (9). 



Mr. R. M. Johnston has given a large number of 

 figures of plant remains collected by him, and described 

 by Ettingshausen and von Mueller. The association of this 

 flora is rather a curious one; next to such genera like 

 Betuhij which occurs in cold and Arctic climates, or 

 Fagiis, which is essentially a genus preferring a cooler 

 climate, or Quercns and Salix, also genera existinor in 

 temperate cooler zones, we have in Clnnaynonum, Sapo- 

 tacites, or Cassia, genera of essentially a tropical nature. 

 It is very difficult to accept such conflicting evidence as 

 final, and considering the very unsatisfactory state of 

 preservation, I cannot help thinking that somewhere a 

 mistake has been made (10.) 



If it could be shown that the tropical genera have 

 been erroneously determined as such, and that only genera 

 indicating a. cool climate occur, the theory of the glacial 

 origin of the Breccia would gain considerable support. 

 Ill that case the leaf bed series had to be included in the 



(9) At the same time it is pretty certain that a good many of the 

 leaves were fairly macerated when they bi^came deposited in the silt. 



(10) During the discussion that followed the reading of this paper 

 Mr, Rodway remarked that at that time wlien Ettingsliausen determined 

 these leaf-remains, phyto-paheontology was in rather a backward state, 

 a remark with which I heartily agree. When I remember the unsatis- 

 factory state of our knowledge of fossil i)lant remains, even as late as 

 the end of the seventies or the beginning of the eighties, and when I 

 consider the great progress made sincf". it is more tlian probable that 

 Ettingshausen's determinations are more or less wrong. Mr. Rodway 

 stated fossil leaves were usually given the names of tliose recent genera 

 with which tliey liad a general resemblance, a practice which is entire- 

 ly wrong, because, without the knowledge of the fruits or blossoms, which 

 are far more important than the leaves, the determination must always 

 remain doubtful. I think that every jjala^ontologist will agree with 

 this, and that the many incongruities resulting from determining the 

 geological age of a series of beds from jilant remains alone result only 

 from wrong identifications of such remains. 



