THE AUSTRALIAN NATURALIST. 27 
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were obtained in the weathered portion of a very tough lime- 
stone, and consisted of Huomphalus, Bellerophon, Naticopsis(?), 
Ctenodonta, ete. All these fossils were, unfortunately, in a 
very bad state of preservation, but, nevertheless, they were in- 
teresting from the fact that they consisted chiefly of shells 
belonging to the Mollusca,a subkingdom not too well represented 
in the Devonian. At Grassy Gully there is an extensive series 
of rhyolites of Devonian age. ‘hese rocks are very silicious, 
in.some places having the appearance of almost pure quartz. 
Dealing next with the Permo-Carboniferous, we have two 
sub-divisions represented in the district. The Lower Coal 
Measures occur in an isolated patch at Yalwal Creek, under- 
lying the Upper Marine Series, and resting unconformably 
upon the Devonian. They consist of alternating beds of shale 
and sandstone, and attain.a thickness of about 40 feet. One 
horizon about midway in the series, contained fragmentary 
specimens of Glossopteris, Gangamopteris, and Phyllotheca. 
The outcrop of these beds is usually hidden by talus slopes, con- 
sisting of portions of the Upper Marine escarpment above, 
undermined by atmospheric agencies. The Upper Marine 
Series at Yalwal Creek rest upon the Lower Coal Measures, 
but in other localities they lie directly upon the Devonian. At 
Grassy Gully they contain pebbles of the underlying rhytho- 
lites. We traced oue interesting fossiliferous horizon from 
west of Yalwal Creek to Burrier, about 10 miles away. The 
sediments get finer and finer as we go eastward, with evidence 
of the proximity of land allalong. ‘The most interesting points 
along this horizon going eastward were as follows: 
Yalwal Creek.—Coarse conglomerates with large Bpecimens 
of Edmondia nobillissima and Maconia elongata. 
Sugar Loaf, Western Side.—Coarse sandstones, containing 
Spirifer 8, Martiniopsis, Dielasma, etc. 
Sugar Loaf, Northern Side.—Coarse sandstones with Spiri- 
fers, Dielasma Euomphalus, ete. . 
Grassy Gully.—Fine sandstones and mud stones, containing 
Spirifers, Dielasma, Productas, Aviculopecten, Aphanina, 
Pachydomus, Conularia, etc. 
Burrier.—Very fine shales, showing worm tracks, and con- 
taining fossil wood Numerous fossils were obtained, lamelli- 
branchs predominating. On this data I think we can fix the 
shore line of the Permo-Carboniferous sea at the time when 
these particular beds were laid down as running approximately 
east and west just south of the localities we investigated. 
I must mention my indebtedness to Mr. J. G. Youll and Mr. 
R. Condie, who accompanied me on the excursion, and with 
Whom many of the facts and jdeas which I was for tanate to 
collect originated, : 
