176 nORX FA'PEDITION — SUMMARY. 



Wliilst tliis niattoi- is ono upon wliich two contiaiy opinions nrc hold, tlicre e;in 

 bo no doubt ))ut tliat Professor Tato's botanical roijions, cspocially takini:;- into 

 account the existence of two sulisidiaiy divisions in liis larger Euronotian I'ogion, 

 indicate a most impoi'tant addition to our knowledge of the general features and 

 relationships of the Australian flora. 



As Professor Tate stated in his address " On the Influence of Physiographic 

 Changes in the Distribution <>i fjifc in Australia," his work had reference mainly 

 to the flora and that in the case of the fauna it yet remained to zoologists "to fuse 

 the species into geographic groups." 



Inasmuch as our present knowledge of the Central Fauna is now considera,bly 

 more complete than it was before the Horn Expedition an<l that in the case of 

 certain lai'ge and imjioitant grou])S such as the I\Tannnalia and Lacertilia we are 

 now better a,ble to Judge of the relationship of the fauna of various parts 

 of the continent, it may be woith while both to indicate the general relationships 

 of the fauna of the central area and to attempt to outline certain general faunal 

 regions into which probably the continent may be divided. 



In certain respects the fauna, stands in strong contrast to the flora. We lind 

 no great Autochthonian region oceupying tiie western and south-western part of 

 the continent. There is amo)igst the higher forms no series of characteristic 

 Australian animals, unless it be to a certain extent amongst the lizards and l)irds, 

 whieh can be considered as having l)een lai'gely represented and developed in this 

 westei'u area during its long period of isolation, in fact amongst mammals it would 

 seem, judging by their pi'esent distribution and the almost entire aljsence of any 

 wiiich may be regarded as at once primitive and peculiar to the west, that the 

 latter did not actually possess any when it flrst became separated oil' from the east 

 in the Cretaceous period during the deposition of the Rolling Downs foi-mation. 



In Australia we have thus an ancient westcnai floi'a which contained repre- 

 sentatives of the forms upon which the present floi'al regions are based whilst the 

 same region probably did not contain many repi'esentatives of the more highly 

 de\-eloped animals upon the present ilistril)ut:ion of which fa.unal i-egions must be 

 ja.rgely based, though at the same time it contained i-epi-es(Mit;itives of lower groups 

 which have also to be taken into account, the membei's of cei'tain higher gi-oups 

 oidy reaching it at a later jteriod. 



Hence it is that the floral and faunal areas of the continent are, in cei'tain 

 important respects, fa,r from being c^o-incidcint. 



