The substance of the following treatise was originally written as a dissertation for the Conington Prize in 1897, and I had at first intended to defer its publication for some time, in view of the accessions of new material which the excavations conducted each year in Egypt are continually bringing to light. It was represented, however (and that by one Whose judgement I was bound to respect), that, although the work might gain in absolute accuracy by such a delay, yet its usefulness to students would be greater if it were published now, as enabling them to assimilate the new material for themselves. Consequently it is with out any idea oi having reached finality, but rather as an assistance to investigation, that this book is now offered to the consideration of students of palaeography.