181 
higher heds become more numerous. In Africa there is on about the same 
horizon a true Coal Measure flora, while in India, below the Gondwana 
System, there is nothing to show distinctly a Carboniferous age of the 
respective heds. The Productus limestone, however, in the Salt Mange, and 
the Productus heds in Afghanistan, are, partly at least, representatives of 
the above Carboniferous beds. 
3. The most important phenomenon within these various deposits is 
the conglomerates or boulder beds,* about the origin of which there is now 
the general opinion that they have been deposited through the action of ice 
in one form or other, the manner of deposition being such as to force upon 
one this kind of explanation, and besides this there have been found 
polished and ice scratched pebbles and boulders within these beds. This 
circumstance would, of course, indicate a rather general change of climatic 
conditions over Australia, portions of Africa, India, &c., towards the close of 
the Carboniferous Epoch. Put I do not think that it was contemporaneous 
over that whole region, and it appears to me that it set in first in Eastern 
Australia (New South Wales), destroying the Carboniferous flora at an early 
date, while in Southern Africa we find still a Carboniferous or Coal Measures 
flora of a higher stage, and only hereafter the change of climate appears 
to have taken place there. 
4. When the conditions of ice action ceased there appeared in Africa, 
India, Victoria, New South Wales, &c., a luxuriant flora of a peculiar 
character, which was, however, foreshadowed by a few forms in the Lower 
Coal Measures in New South Wales. In this period falls the deposition of 
the Karoo Formation in Africa, the Gondwana System in India, Newcastle 
beds, &c., in New South Wales, Bacchus Marsh beds in Victoria, and so on. 
Several of these deposits contain thick and important coal seams. 
5. The age of the various deposits can be fixed with approaching 
certainty, or at least with great probability when we start from the horizon 
of the boulder beds. Assuming these to fall towards the close of the Carboni- 
ferous Period, then the age of the beds above and below can be approximately 
fixed. 
The following General Tabular View may represent all the relations 
discussed in the preceding pages. 
[See foot-note, p. 28.- R. E., jun.] 
