SOIL OK SURFACE-MATTER. 237 



in such places as Devonshire, where after dry 

 weather clouds of dust are often raised off the pas- 

 tures. Wynne, in his description of the geology of 

 Kutch, India, when describing the alluvium, proves 

 the soil-producing powers of wind. In the early 

 part of the memoir he mentions the extreme 

 denudation the rocks suffer from the winds, and 

 writing of the alluvium, he states : " The deposits 

 frequently resemble those of rivers ; but there are 

 no large rivers in Kutch, and the small intermittent 

 streams which it possesses would have to wander 

 laterally to a great extent in order to cover the 

 country with such detritus. They only appear to 

 have changed their courses in a few localities near 

 the coast, and their valleys, though small, are 

 generally single and separate, from the hills to the 

 sea." 



Some of the Kutch alluvial deposits are salt, 

 sometimes two or three feet in thickness, due to 

 the evaporation of floods of saline water ; others are 

 so impregnated with salt (Kara and Kuller) as to be 

 incapable of producing vegetation ; while on others 

 (Laana) there is a scanty growth of plants. 



Other soil-formers that are rarely thought of are 

 the ants. These workers, although such pigmies in this 

 country, and therefore, compared with the earthworms, 

 less capable, individually, of work, are so numerous 

 and energetic, that in the special places to which 



