422 Cottesivold Naturalists Club. 



E. meridionalis into tlie sub-genus Euelephas ; (&) the necessity for 

 establishing a new species, called by Mr. Gunn Leptodon, from the 

 fineness of the enamel ; (c) the variation of the E. antiquus from the 

 Post-glacial Mundesley lacustrine bed, and (d) the probable deriva- 

 tion of the E. antiqims from an old type of the E. Africanus in the 

 Norwich Mammaliferous Crag. 



CoTTESWOLD Naturalists' Field-club. — This club met for the 

 second time this season at Mickleton Manor, near Campden, by 

 invitation from Sir Maxwell and Lady Steele Graves. 



After dinner, Dr. Paine, the hon. secretary, read Mr. Bravender's 

 paper " On the Watershed of the Upper Thames." 



The subject of water supply having of late so much occupied 

 public attention the author offered some account of the watershed of 

 the Upper Thames, between the sources of the Thames and Oxford. 

 The com-se of the Thames is eastward, and it is fed by many small 

 rivers and brooks coming from the north and south. The highest 

 area of the watershed of the Thames is 74 square miles. The 

 author described in detail the various streams which feed the Thames 

 above Oxford, the largest the Ock, draining an area of 100 square 

 miles, falls into the Thames at Abingdon, below Oxford, and beyond 

 the district named. The watershed on the south side of the Thames, 

 containing 123 square miles, yields a smaller supply than the same 

 area north of the river. The dip of the strata is south-east, descend- 

 ing from the Thames on the south side, but towards the Thames on 

 the north side. The surface of the country slopes from the Chalk 

 Hills towards the Thames, and the water which immediately runs off 

 reaches the Thames, but at a slower rate than that from the north. 

 Part of that which is absorbed by the soil, and part which is lost in 

 the streams in the passage over open and porous beds, sinks through 

 those porous beds to the upj)er surface of the tenacious beds of the 

 Oxford clay, Kimmeridge clay, and the Gault, and the water de- 

 scending the plane of stratification in a contrary direction to that of 

 the river is lost to the Thames. The same remarks refer to the 

 watershed of the Ock. The area of the watershed of the Upper 

 Thames thus described is 875 square miles, and is made up as 

 follows : — 



WEST OE THE THAMES. 



Swillbrook and Thames Head 



SaUARE MILES. 



... 74 



NORTH OF THE THAMES. 





The Churn 



... 73 



Ampney and Marston brooks 



... 32| 



The Coin 



... 87 



The Leach 



... 36| 



The Brampton and Thames district ... 



... 119 



TheWindrush 



... 141 



The Evenlode 



... 189 





752 



