IN Louden's Magazine of Natural History, 1835, pp. 40–53, there appears an article entitled “An attempt to classify the ‘Varieties’ of Animals, with observations on the marked Seasonal and other Changes which naturally take place in various British Species and which do not constitute Varieties”, by Mr. Edward Blyth. Certain passages contained therein seem to indicate that the principle of natural selection, or the survival of the fittest, was clearly understood by Blyth in 1835, and, further, that he recognised its application to artificial selection. Moreover, he demonstrates the idea of sexual selection in one of its bearings. I have therefore considered them of sufficient interest to be made public, as it appears, they have hitherto escaped notice.