INTRODUCTION. 
THE limited space available in the National Museum for the exhi- 
bition of the geological collection of rocks makes it impossible at 
present to display more than one suite of specimens. To render 
the collection complete, it should comprise three sets—one of which 
should be arranged lithologically, to illustrate the composition, 
structure, and physical aspect of the rocks; a second, stratigraphi- 
cally, to illustrate the order of succession of the several formations ; 
and a third, topographically, to illustrate their geographical dis- 
tribution. 
In this collection the stratigraphical arrangement has been 
selected, as best adapted to afford special and general knowledge 
of the characters and aspect of the various rocks met with in each 
formation, while the colored label on each specimen, when compared 
with the similarly colored geological maps, shows approximately 
their geographical distribution. There are two labels on each speci- 
men : the colored one indicates the formation to which the specimen 
belongs, the locality, and the reference number on the maps; the 
other is the Descriptive Catalogue number for each formation. 
Some of the specimens show examples of the fossils characteristic of 
the formation to which they belong ; but a separate and complete 
collection of fossils, arranged stratigraphically, and named and 
described by Professor McCoy, is being prepared, and will fully 
illustrate the Paleontology of Victoria. 
The minerals are also arranged as a separate collection, and 
numbered consecutively to agree with the Descriptive Catalogue. 
The published geological quarter-sheet maps, referred to on 
the specimen labels, are exhibited on the walls contiguous to the 
cases. Each map represents fifty-four square miles of country, and 
a copy of the geologically-colored sketch-map of the whole colony, 
on a scale of eight miles to one inch, is also exhibited, On the 
above-mentioned maps are letters and numbers—thus (E8) — which 
