With the exception of the corrections detailed below and some minor corrections (missing periods, commas, etc.) which were made but are not listed, the text presented is that in the original printed version. The illustration labels were originally presented at the bottom of the containing page; but have been moved beneath the illustrations. Typographical Corrections Page xi: Ophiopolis => Ophiopholis Page 4: diferent => different Page 21, 101, 127, 131, 148: so called => so-called * * * * *