PREFACE. 
tenance my suggestion as to the Oligocene Tertiary age of the 
Schnapper Point and Muddy Creek beds in which they are found. 
Then follows a plate of great interest as illustrating two Tertiary 
species of Trigonia, a genus hitherto only known as abounding in 
the Mesozoic rocks of many parts of the world, and at the present 
time in Australian seas ; but the complete absence of which, in the 
intermediate Tertiary periods, in all localities examined, was looked 
upon by geologists as a most curious exception to the general 
paleontological law of the distribution of genera in time—an ex- 
ception which we can now remove. The remaining figures on this 
plate illustrate three of the very few ‘still living or recent species 
found in our Miocene and Oligocene Tertiary rocks ; one of these 
is the most common bivalve in the Geelong and Schnapper Point 
beds, and lives now, not in our seas, but in those of the northern 
part of New Zealand. The second is a Limopsis, long known as a 
common Miocene Tertiary species in many European localities, and 
of special interest from having been dredged up alive in the Arctic 
Ocean. Its recognition as one of the most abundant of our Miocene 
bivalves was inexplicable until lately Prof. Wyville’ Thompson 
dredged it alive from extreme depths continuously along the ice- 
cold bottom extending from the Arctic Ocean, under the Tropics, 
into the Southern Ocean farther south than Melbourne. The third 
species is a Limopsis hitherto only known from a few living speci- 
mens, dredged from 120 fathoms off the Cape of Good Hope by 
Admiral Belcher, but which I have been able to certainly identify 
by direct comparison as one of our commonest fossils in several 
Victorian Miocene and Oligocene strata. 
The last plate is devoted to further illustrations of additional 
species of Graptolites* from our goldfield slates, identical with 
* On receipt of the Ist Decade, Mr. Selwyn writes to remind me that in June 1856 he 
brought me a specimen of a Graptolite, six months before those of Mr. Panton were received ; 
so to him, and not to the latter, must be awarded the merit of finding the first Graptolite which 
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