i6 
A. GIBB MAITLAND, F.G.S. : 
of its course flows at the foot of the great Kennedy Range 
escarpment, there are many sections which show the nature 
of the beds beneath the sandy series. They consist of a 
thickness of fossiliferous limestone, which dips at gentle 
angles of from 5 0 to 8° to the westwards. This limestone, 
which can be followed by the eye across country for a gieat 
many miles, is the equivalent of that met with in the deep 
bore' at Pelican Hill, near Carnarvon. Many excellent 
exposures of it are to be seen in the range through which 
the Wvndham and Arthur Rivers flow. A very tine section 
of this limestone is to be seen in the gorge through which 
the Wyndham River passes, near Survey Traverse Station, 
No. 56. The sections in the Arthur River above the range 
give a fairly complete section of the basal members of the 
Permo-Carboniferous Rocks, and are in addition of con- 
siderable scientific importance. Between the Arthur Gorge 
and Barragooda Pool there are one or two exposures of the 
glacial boulder bed, which is seen to lie beneath the fossili- 
ferous limestone. 
As it will be convenient to have a name by which to 
designate this important geological horizon, it is proposed 
to use for it the term “ Lyons Conglomerate,” which is the 
official designation of the Land District in which it was 
first discovered, and where it is so well developed. 
Figure. 2, Plate If, gives a section of the strata in the 
valley of the Arthur River, showing the stratigraphical 
relationship of the boulder bed. A section on the southern 
bank of the Arthur River shows large striated boulders 
embedded in a very calcareous clayey matrix ; the bed, 
as may be seen in the photograph (Plate HI. Fig. 3), is not 
very thick, but bv weathering in situ its debris occupies 
a vddth in places of about a mile. It is very seldom that 
the bed is actually seen in situ, though its presence is al- 
ways indicated by the heterogeneous collection of boulders, 
which strew the surface and which result from its weathering. 
The various rocks which form the boulders in the “ Lyons 
Conglomerate ” consist of quartzite, granite and basic rocks, 
of the type which characterises the older strata immediately 
underlying the Permo-Carboniferous beds outcropping to 
the eastward. 
The boulders and fragments are of all sizes from an 
inch up to several feet in diameter ; some of the pebbles 
are beautifully striated ; a photograph of a scratched 
quartzite pebble from this locality is shown in Figure 4, 
Plate III. 
The thick stratum of limestone above the boulder bed 
in the Arthur River contains such a series of fossils as 
clearly indicates its geological horizon, viz. -.—Evactinopora 
