C/HAP. XII.] SOILS AND SUPERFICIAL DEPOSITS. 181 



Alluvium of fluviatile origin occupies the delta of the Cauvery to 

 the South of the Coleroon branch, a large part of the flat tract inter- 

 vening between the Guddalum and the Ariancoopura, and narrow strips 

 bordering the larger streams. It is usually a pale sandy loam, and 

 whenever a supply of water is obtainable, is brought under paddy cul- 

 tivation. In many places it is now above the flood levels of the coun- 

 try, and in the alluvial and regur covered tract to the South of Verda- 

 chellum, the fluviatile alluvium, which borders the Mani Mukta and 

 the Vellaur, is at a higher level than the regur which occupies the 

 intervening area. In a section of the river bank at Sattyavadi, on the 

 Vellaur, 20 feet of fluviatile alluvium is exposed, resting on 3 or 4 feet 

 of regur. The alluvium is highest close to the bank of the river, and 

 extends thence (at the place mentioned) about 2 miles to the North- 

 ward, the surface gradually declining to that of the regur. A section 

 across the alluvial tract at Sattyavadi would probably show the rela- 

 tions of the soils to be such as are exhibited in the accompanyino- 

 section. Fig. 17. . 



Fig. 17. Diagraji Section across the valley of the Vellaur Eivee, 

 Mani Miikta, E. Vellaur, R. 



! - i 



Verdachellum. Sattyavadi. 



a. a., Fluviatile alluvium : r. ?•., regur : ?. Z., red soil (Ferruginous sand). 

 The relations of the alluvium of the Cauvery to the regur are pre- 

 cisely the same as the above, and the two deposits may be seen in 

 contact at several places on the margin of the fluviatile tract. On the 

 North of the Coleroon branch of this river little or no alluvium is met 

 with below a point a few miles below Lalgoody ; beyond this the left 

 bank of the river is formed by the regur which is seen at a higher level 

 ihan the fluviatile alluvium of the delta. 



