Reports & Proceedings—Hdinburgh Geological Society. 137 
was 1 foot. It is not continuous over the area, but occurs in patches 
on slightly raised ground. Some parts of this deposit may be of 
commercial value for use as an abrasive. 
A microscopic examination of the deposit was made by Mr. G. West, 
of the Botanical Department, University College, Dundee, who makes. 
out a list of thirteen genera of diatoms. 
2. January 19, 1916.—Dr. Robert Campbell, President, in the Chair. 
1. ‘Notes on the Former Courses of the River Devon.” A suggested 
Evolution for part of the River System of Fife and Kinross. “(With 
lantern illustrations.) By J. E. Wynfield Rhodes, B.Sc., M.I.M.E. 
In this paper an attempt is made to trace out the evolution of the 
valleys of the Rivers Devon, Eden, Leven, and their tributaries. 
Starting from the assumption that the original or consequent 
drainage was E.S.E., an assumption justified by the study of other 
districts on our eastern seaboard and in entire harmony with the 
evidence obtainable locally, the positions of two of the original 
streams A and Bare postulated. This constitutes the first stage in 
the evolution, and the gradual development of our present river 
system in this area is shown to occur in four subsequent stages. The 
course of stream A is marked by the following valleys: Glen 
Lednock, Glen Eagles, Glen Devon, the Gairney Water Valley, 
Blairadam windgap, and the Chapel Burn. Stream B was parallel 
to it, and its site is marked by the S. Queich, Loch Leven, and the 
Lochy Burn. Stream A is beheaded at Muthil, thus producing the 
obsequent Glen Eagles Valley, and near Cardenden by the River 
Ore, a tributary of stream B. Subsequently a stream cutting back 
along the Ochil fault beheads stream A at the Crook of Devon and 
the River Devon is produced. In the next stage the strike stream 
Eden beheads both A and B and develops the Plain of Kinross ; 
Blairadam and Ballingry windgaps are thus produced. Finally, in 
the Glacial period, Loch Leven is produced by a drift dam at. 
Mawearse, the waters of the lake escaping by the Leven Valley. 
2. ‘‘Veining and Metasomatism in Basalt at Upper Whitfield, 
near Macbiehill. ”. (With lantern illustrations.) By T. Cuthbert 
Day, F.C.S. 
The author recognizes the great variety of ways in which veining 
may occur in igneous or in sedimentary rocks, and does not pretend 
to put forward a theory of uniform application. He merely describes 
a particular case, and seeks to maintain that the veining in the basalt 
at Upper Whitfield has not been caused by infiltration of mineral 
matter into ready formed fissures or dislocations in the basalt, but by 
a methodical replacement of the basalt along the layers of exfoliation, 
the basalt itself being removed piecemeal and its place taken by 
veining material. An example of what might be considered as 
metasomatism in the same basalt is also described, the prime cause of 
the alteration being due to some defect in the part of the basalt at the 
time of intrusion which rendered it liable to attack by mineral 
solutions. An attempt is made to explain the order of the changes 
