The relationship of geomorphic and climatic history and formation of tlie ferruginous soils, formed on the acidic Peninsular Gneiss, of tlie Mysore Plateau, India. is discussed. The profiles studied are found on two different land systems. Tlie soils of tlie older, fairly smooth landscape are composed of colluvium over truncated laterite profiles. with a gravel layer and a prominent kaolin layer over tlie weathered rock. These soils show an accumulation of pedogenic liaematite grains in the sand fraction and lime considerable kaolinite and amorphous feni-aluminosilicate minerals in the clays.The soils of the younger, rugged landscape have similar clay mineralogy. but du not have a gravel layer, or haematite grains. The influence of the coarsegrained parent rock is seen in the large amounts of quartzgravel. The absence of granulation is attributed to lack of accumulation of iron.The soils have been formed in an earlier, more liuniid climate than prevails today. The original laterite profiles were formed on a plane surface, and subsequent change in climate has led to change in the land forms and dissection. Truncation of tlie profiles was followed by deposition of red colluvium over the resistant ferruginous layer.These ancient soils do not fit the criteria for Oxisols in tlie US. classification. but t'it well in the French system as 'Sols Ferrallitiques', subclass 'fiablement disaturcs en (13)'. The soil from a low lying area, formed from colluvium under hydroinorpliic conditions. is classified as 'Vertisols et Paravertisols'.

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