There is no royal road to the knowledge of Fungi; and it is impossible, with any regard to scientific accuracy, to avoid the use of language which at first sight may be repellent. It need not, however, be so in reality. The careful mastery of a few scientific terms by the aid of the Glossary (end of vol. ii.) will enable those who have not hitherto studied the subject to use the descriptions, not only with ease, but with much greater satisfaction in the identification of species. This is particularly the case in regard to Edible and Poisonous species. Any description of general appearance, which omitted scientific details, might be most misleading. The species must be carefully identified by means of the descriptions. Comparatively few of the Agarics are used as food. Probably a much larger number are either edible or harmless.<br><br>It has been usual in the descriptive literature of Mycology to give a diagnosis, followed by a description of each species. This may be a convenient method in letterpress to illustrations; but in a work designed for practical use, it involves extensive repetition.