Natural History of Victoria, 147 
showing here, as in Europe, the gradual cooling of our globe 
during the Eocene and Miocene periods. To refer again to the 
mistaken popular theory alluded to in the first paragraph, in 
which the suggestion is dwelt on of the present existence in the 
Australian seas of the possibly oolitic Trigonig, I think it of 
great interest to state that the four living species of Trigonia 
seem to have been created only during the modern period, and 
are represented in our Tertiary deposits by a totally distinct 
species—the Trigonia semiundulata (M‘Coy). 
5. Recent Period. 
As the space assigned to me has been far exceeded, I can only 
offer a few remarks on the Existing or Recent Natural History 
of the country, which is so much better known than that which 
has preceded. The recent Mammalia and Birds of Australia 
are so fully known from the admirable works of my friend Mr, 
Gould, that I shall not allude at all to them, further than to 
correct an error which seems to be universal in books, and occurs 
even in the memoirs of Mr. Ronald Gunn, of Tasmania, namely, 
that the large Dasyurus maculatus is only found in Tasmania, 
and not on the Australian mainland. I have had seven or eight 
specimens collected for the National Museum from the Yarra 
Mountains and other hilly localities within thirty or forty 
miles from Melbourne. Contrary to my preconceived opinion, 
I have satisfied myself that the native Dog (Canis Dingo) is 
truly an indigenous animal, both from its mereasing in numbers 
(with little variety) towards the interior of the continent 
remote from man, and from having identified its bones mingled 
with those of recent and extinct animals all in one state of pre- 
servation in the bone-caverns recently opened beneath the basalt 
flows at Mount Macedon. 
Of Reptilia the great Hydrosaurus varius, called Iguana by the 
colonists, and often 5 feet in length, is the most important of 
the Lacertilia ; several smaller types are also common near the 
coast, as the Hinnulia teniolata, Cyclodus gigas, and Grammate- 
phora muricata; and the G. barbata and Trachydosaurus rugosus 
(called Dew-lizard by the colonists) become gradually common 
as you approach the warmer country near the northern boundary 
of the colony, butdo not occur, [ believe, south of the dividing 
range. Of Batrachia the Ranhyla aurea is the exceedingly com- 
mon Green Frog of the country, and is so unlike Hy/a in its 
habits, which agree completely with Rana, that its generic sepa- 
ration from Hyla (contrary to the opinion of several able autho- 
rities) is I think quite necessary. In two other Frogs, species of 
Lymnodynastes, the unexpected habit is found, in this arid, watere 
é 10* 
