Land cud Fresh-water Vertebrates in Victoria. 51 



GENERAL CONCLUSIONS. 



Ever since it was formed, or existed in anything like its 

 present condition, Bass Straits must have presented a very 

 formidable mechanical barrier to the passage of all land and 

 fresh-water Vertebrates unfurnished with wings. On the other 

 hand, seeing the exceedingly wide continental distribution of 

 such slow-travelling animals as Irichosums vulpecula, Trachy- 

 saurus mgosus, Egernia zvhitii, Liaiis burtonii, it seems plain 

 that the Dividing Range in its present state cannot have acted 

 at all as a serious mechanical barrier. But the Dividing Range 

 has been felt in its action on the rainfall. Widely divergent 

 climatic conditions have thus been produced, yielding a humid 

 region in the south-east and a dry region in the north-west. 

 Where the nature of the soil was favourable great forests have 

 nourished, as in Gippsland and in south-west Tasmania. Thus in 

 the one district we have excess of moisture and abundant shade, 

 and in the other lack of moisture and consequent excess of sun- 

 shine by day and of radiation by night, all potent factors in 

 animal life. Hence two faunas suited to the two regions. Where 

 this barrier is most perfect the separation of the districts is most 

 sharply marked ; in the west, where it gradually disappears, the 

 faunas merge to some extent, but as the presence of the range 

 intensities the humid conditions on the coast side, there is less 

 mingling of forms than might at first have been expected. 



As we have seen from the tables, the characteristic assemblage 

 of animals of the drier area comprises the Jerboa-Rats (ffapaloiis) 

 among the Rodents ; the Jerboa Pouched Mouse (Antechinomys), 

 two other Pouched Mice (Phascologak calura and Sminthopsis 

 murina), and Geotf'roy's, or the Black-tailed, Native Cat (Dasy- 

 urus geoffroyi) ; the Striped Bandicoot (Peratneles Iwugainvillii, 

 var. fasciata) and the Pig-footed Bandicoot {Chieropus castiuiotis) ; 

 the Wallaroo (Macropus robustus) and Great Red Kangaroo (A/, 

 ritfus), the Hare Wallaby (Lagorchestes kporoides), and the 

 Bridled Wallabies (Onychogale frenata and O. lunata) among 

 the Marsupials ; the Murray Tortoise (E my dura macquaria) ; 

 the Blind Snakes (Typhlops), Tree Snake (De/idrop/iis), and the 

 two Pythons, the Carpet Snake {Morelia variegata) and Diamond 

 Snake (Af. spi/oks), and among venomous snakes the genera 



4A 



