This paper may be regarded as a notice of those portions of the recently published “Manual of the Geology of India,” by Messrs. Medlicott and Blanford, which describe, or in any way relate to, the extensive lateritic deposits of Peninsular India. The hypothesis (or, more properly, the modification of an antecedent hypothesis) herein offered, in the hope that it may be tested by the Indian geologists, is based on extended examinations of deposits believed to be analogous, and has been found to satisfactorily explain the phenomena observed.