THE CLASSIFICATION OF PLANTS. 407 



•was but a slight alteration of that of Eivinus. That of 

 Tournefort, which was promulgated about the rear 1695, was 

 for a considerable time the favourite system of all botanists ; 

 but it was ultimately superseded hj that of Linnaeus. About 

 8000 species of plants were then known to botanists ; these 

 were distributed hj Tournefort into twentv-two classes. He 

 first diA'ided plants into two di-s-isions ; one of which comprised 

 herbs and under-shruhs, and the other trees and shrubs; each of 

 these divisions was then divided into classes, which were charac- 

 terised chiefly according to the form of the corolla. Many other 

 systems were devised which were simply alterations of the fore- 

 going, as that of Pontedera. Magnolius, however, framed a 

 system entirely on the calyx, while Gleditsch attempted one in 

 which the classes were founded on the situation of the stamens. 

 All the above systems were, without doubt, useful in their day, 

 and paved the way for those of a more comprehensive nature, 

 such as that of Linnaeus, which, being still in use to some extent 

 requires to be particularly examined. 



LiXNiEAN System. — This celebrated system was first pro- 

 mulgated by Linnaeus in his " Systema Naturae," published in the 

 year 1735. It has been somewhat altered by subsequent 

 botanists ; but, in all its essential characters, the Linnaean 

 system, as now adopted, is the same as de^^sed by the great 

 Linnaeus himself. In describing this system we shall adopt the 

 arrangement of the present day. 



The classes and orders in the Linnaean system are taken exclu- 

 sively from the essential organs of reproduction, the sexual nature 

 of which Linnieus had just before clearly estabhshed ; hence 

 this artificial scheme is commonly termed the Sexual System. 



Classes. — In this system plants are at first divided into 

 Flowering and Flowerless, the latter of which constitute a class 

 by themselves, under the name of Cryptogamia ; while the 

 former, called the Phanerogamia, are divided into twenty-three 

 classes — the characters of twenty of these depend upon the 

 number, position, relative length, and connection of the stamens ; 

 while those of the other thi-ee are derived from the imisexual 

 nature of their flowers. The names by which the classes are 

 characterised are all derived from the Greek, and express their 

 distinctive peculiarities. 



The first eleven classes comprise all hermaphrodite flowers 

 the stamens of Avhich are all distinct from each other, and about 

 the same length, or, at all events, neither didynamous nor 

 tetradynamous. The individual classes are distinguished by the 

 absolute number of such stamens, and their names are formed 

 by the combination of the Greek numeral expressing the num- 

 ber, with the termination andria (from a.vi]p, a man or male), in 

 reference to their oflSce in the process of fertilization. Thus : — 

 D D 4 



