There are a number of other manuscript herbals in existence, illustrated with interesting figures. The Library of the University of Leyden possesses a particularly fine example[33], which is ascribed to the seventh century A.D. [Illustration: _Plate XV_ ‘Phasiolos’ = Bean [Dioscorides, Codex Aniciæ Julianæ, circa A.D. 500]. _Reduced._] This work contains coloured drawings of exceptional beauty, which are smaller than those in the Vienna manuscript, but quite equally realistic. It is however with the history of botanical figures since the invention of the printing press that we are here more especially concerned. From this epoch onwards, the history of botanical illustration is intimately bound up with the history of wood-engraving, until, at the extreme end of the sixteenth century, engraving on metal first came into use to illustrate herbals. During the seventeenth century, metal-engravings and wood-cuts existed side by side, but wood-engraving gradually declined, and was in great measure superseded by engraving on metal. The finest period of plant illustration was during the sixteenth century, when wood-engraving was at its zenith. Botanical wood-engravings may be regarded as belonging to two schools, but it should be understood that the distinction between them is somewhat arbitrary and must not be pressed very far. One of these may perhaps be regarded as representing the last, decadent expression of that school of late classical art which, a thousand years earlier, had given rise to the drawings in the Vienna manuscript. Probably no original wood-cuts of this school were produced after the close of the fifteenth century. In the second phase, on the other hand, which culminated, artistically, if not scientifically, in the sixteenth century, we find a renaissance of the art, due to a more direct study of nature.