Two volume set in clamshells and slipcases. Both volumes include an 8 page pamphlet "Horticultural Colour Chart" by Robert F. Wilson. 100 color sheets each with examples of the color, history, equivalency. Edges of plates have curled up due to placement in claimshells. Also laid in is a viewing mask. Stamp of previous owner's name and address in each volume stamped on inside claimshell.