THE fragmentary Introduction which was begun by Dr Hort in 1872, and continued at two later dates, gives in part the history and scope of the present volume; but the revision indicated in the opening paragraph was not completely carried into effect. The first two Lectures were set up in slip in 1872, and after careful revision were passed for press at the close of 1874. The first four sheets were printed off (pp. 1—80), the remainder of Lecture II. remained in slip, and pencillings on the copy suggest that some enlargement of the conclusion was in contemplation. The third Lecture has been printed partly from the original MS. (pp. 95—107; 146—8), and partly (pp. 108–146) from a MS of later date. The fourth Lecture has been printed as it was originally written. The MS. has not received any later additions, but something appears to be wanting on p. 166. The ‘Notes and Illustrations’ were taken from collections made for the Lectures and for the revision of them, and will serve in some measure to illustrate the wider range which was designed for Lectures III., IV. (p. xxvii.).