Allow the grasses to soak for some time in a very hot and strong solution of aniline dye in water. Those dyes which are not soluble in water may be dissolved in spirit, and the solution added to water. Some aniline dyes will colour direct in this way, but others require a mordanting or fixing agent. For fixing basic dyes, such as magenta, methyl violet, etc., the grasses should first be soaked in a hot solution of oak bark or of sumach. Many pretty shades may be obtained by first soaking in a hot solution of picric acid, and then iu magenta, methyl violet, methylene blue, etc. For green, picric acid and indigo extract may be used. In all cases the dye solution should be strong and hot, or the dye will not penetrate. The grasses should be quickly dried after soaking in the colours.