The spores of ground-growing kinds, when shed upon the ground, are washed by rains along the natural drainage; therefore, when a specimen of one of these kinds is found, it is well to look up and down the natural water-shed, and follow it. Good reward will usually come of it. Few fungi are strictly solitary. Careful observation of the habitats of the various genera and species will enable the student to know what may and may not be expected in a particular locality, and will save many a hunt. When an unknown species is found, collect it carefully, examine it closely, note all its features. Determine to which division of fungi it belongs. If to the gilled family (Agaricaceæ) obtain the color of the spores (see directions). Look at the chart “Tabular View of Genera of Agaricaceæ,” Plate I, p. 2 (after W.G. Smith, but enlarged, redrawn and emended). If the spores are white, it belongs to one of the genera in the first column—Leucosporæ; if pink, to one in the second column, and so on. It is often difficult to determine the spore color, because spores vary through many shades of the typical color. What are called white spores may be creamy, dirty, yellowish or brownish-white; pink spores will vary from almost white to reddish and salmon-color; brown spores from light-ochraceous through cinnamon to rusty; purple spores from dark-violet to purplish-black. Experience alone will enable the student to decide which color series is present. The Genera Charts, preceding the five different color series, show typical spore colors only. Again, authors describing the species frequently fail to see colors alike; if they do, their names for them frequently vary. For instance, few persons will agree upon a color expressed as “livid.” The color system principally used by botanists is Saccardo’s “Chromotaxia,” costing fifty cents. It is decidedly inadequate. Ridgway’s “Nomenclature of Colors for Naturalists” is far better, but it is out of print and obtainable only at the principal libraries. “The Prang Standard of Color” is the most complete ever issued, but it is inapplicable to existing descriptions of fungi. [Sidenote: Make and Preserve Spore Prints.] Take, to print upon, sheets of Bristol-board or any stiff, hard-surfaced white paper 6×9 inches or larger. Cut a round hole, four inches in diameter, in one of the sheets. Use this as a stencil. Lay it upon a print-sheet and where the opening occurs, paint with a weak solution of gum arabic—⅛ oz. (one teaspoonful) to one pint of water. Dry the print-sheets.