2o6 
Mines and Mineral Statistics, 
of tlie Dipiioous type, and it is only a proof of the incom- 
pleteness of the palieontologieal record, that we haA'C to derive 
all our information regarding it from only three so very distinct 
periods of eiistence. The Dlpt^oi offer the most remarkable 
example of persistence of organization, not in fishes only, hut in 
vertebrates. On a former occasion I have shown that numerous 
recent species of fishes have survived from the period of the 
geological changes which resulted in the separaiion of ^ the 
Atlaiitic and Pacific hy the Central American Isthmus. lu Cera- 
todus we have now found a qenus which, as far as e\idenco goes, 
persisted unchanged from the IMesozoic era ; and in the 
V, family, the nearest ally of which lived in the Paheozoic epochs.” 
This' is a most valuable link in the connection of the old geologic 
periods with the present era, and a tit conclusion for the account 
above given, however, unworthy that account may he, ot Quater- 
nary and llccent Accumulations. 
No notice in this Memoir has been taken of igneous rocks ; hut 
it may be suitable to state that there is in all the various 
vSedimentary formations noticed distinct evidence of the presence 
of igneous action {lufdro-iyneon^i rather), and their transmutation 
through such and allied 'agencies has left an impress upon all 
the rocks more or less concerned. 
No particular or special reference could enter into the object 
for which this iMemoir is written ; hut it is to he understood that, 
though all the rocks have undergone a transmutation, this does 
not constitute what geologists have understood by “lMetamor]jhic * 
system, of Avhich, as before said. New South Wales, at least, 
shows little or no visible trace. ^ ^ ^ 
2 June, 1875. 
P S —In order to explain the position of Glossopterls in_ the 
Palaeozoic marine deposits, I have appended two vertical sections, 
one, hy myself, previously published in the “ Transactions of the 
EoyarSoc’iety of Victoria, 1801,” illustrating the coal seams at 
Stony Creek ; and the other showing tlie deposits at Greta, near 
Anvil Creels whicE has hcon reduced from one on a larger scale, 
kindly supplied to me hy Mr. James Fletcher, Colliery Viewer, 
to whom I am also indebted for a collection of strata, the charac- 
teristics of which I have given after careful examination of them 
and of other specimens collected hy myself on former occasions. 
Tlic latter section illustrates a Avidc area on that part of the 
Hunter liiver. No, 2 is about 10 miles Avest of No. 1. 
30th June, 1875. 
