PREFACE.

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of leading into the depths of botanical philoso-phy, whether physiological, systematical, or cri-tical, any student who should be desirous of pro-ceeding so far. A volume of this size can indeedbe but elementary on subjects so extensive; butif it be clear and intelligible as far as it goes,serving to indicate the scope of the science ofbotany, and how any of its branches may becultivated further, my purpose is answered. Thesubject has naturally led me to a particular cri-ticism of the Linnaean system of arrangement,which the public, it seems, has expected fromme. Without wasting any words on those specu-lative and fanciful changes, which the most ig-norant may easily make in an artificial system ;and without entering into controversy, with thevery few competent writers who have proposedany alterations; I have simply stated the resultof my own practical observations, wishing bythe light of experience to correct and to confirmwhat has been found useful, rather than rashlyto overthrow what perhaps cannot on the wholebe improved.

As the discriminating characters of the Lin-naean system are founded in nature and fact,and depend upon parts essential to every species