576 TRANSACTIONS OF SECTION C. 



concretionary nodules of carbonate of lime, such as Mr. Lomas had described in 

 connection with the Trias. He was not prepared to admit that the features of the 

 British Trias were due only to wind action ; but in the main they were due to the 

 conditions prevailing in desert regions, where, during monsoon seasons, there may 

 be a heavy rainfall for a limited period, with rivers in Hood, and all the usual 

 phenomena of river action. 



(iv) By Professor Grenville Cole. 



Professor Cole said that in dealing with tlie British Trias they must never 

 forget the great sea eastward, and the likelihood of the establishment of a monsoon 

 system upon its margin. The geographical conditions seemed well suited for this, 

 and an intense rainy season, lasting (say) three months, might easily, year after 

 year, sweep down and redistribute materials which remained dry for the other 

 nine months. Sheets of pebbles, without well-defined water-channels, were com- 

 patible in such cases with general evidences of desiccation. 



3. Notes 011 the Permo-Carhoniferous Coal-fields of AiLStralasia. 

 By Professor T. W. Edgeworth David, F.R.S. 



The author called special attention to the following features: Throughout 

 the whole of Southern Australasia the basal rocks of the Permo- Carboniferous 

 System are either glacial tills resting on striated rock-pavements, or are marine 

 beds with abundant ice-transported boulders scattered through them. In New 

 South Wales and Tasmania the Permo-Carboniferous beds contained an important 

 coal-series — the Greta Series — intercalated between the glacial beds of the Lower 

 Marine Series below and the erratic-bearing beds of the Upper Marine Series 

 above. 



In New South Wales there is a thickness of not less than 6,000 feet of strata 

 separating two glacial horizons, a fact which proves that the glacial conditions 

 must have been considerably prolonged. 



As regards the mode of origin of the seams, nearly all of them repose on 

 uuder-clays penetrated by more or less vertical Vertehraria, and there is a great 

 abundance in the coal of leaves of Glossopteris and Gangamopteris. Most of the 

 coal-seams, at the time when their development was finally arrested, supported a 

 luxuriant growth of conifers referred provisionally by Mr. Arber to Dadoxylon. 



Reference was made to the fact that where the Permo-Carboniferous sediments, 

 as in the type-district near Newcastle in New South AVales, attained a consider- 

 able thickness (14,000 feet in that case) they had been considerably folded, but 

 where they were thin they had escaped folding. 



The curious pseudomorph lately described by New South Wales geologists as 

 ' glendonite,' allied to thinolite and referred to glauberite, is very abundant in the 

 Upper Marine Series of New South Wales. It resembles in some respects the 

 jarrowite described by Professor Miers from Jarrow, and the pseudomorphs 

 dredged from the recent muds in the Clyde river, and referred to gaylussite. 



As regards the quantity of coal exploitable in New South Wales, rough 

 estimates have shown that, if seams less than three feet in thickness and coal at a 

 depth greater than 4,000 feet are left out of account, there remain approximately 

 one hundred thousand million tons, and there is probably an equal amount of 

 Permo-Carboniferous coal available in Queensland. 



4. The Problem of the Palceozoic Glaciations of Australia and So\Uh 

 Africa. By Professor J. W. Gregory, F.R.S. 



The Upper Palaeozoic Glaciations of Australia, India, South Africa, and South 

 America offer one of the most difficult problems in the history of climate. Some 

 of the conceptions of the extent and nature of their glacial beds present such 



