O ON SYSTEMS AND CLASSIFICATIONS. 



cation, which we are too short-sighted to perceive, and too super- 

 ficial to fathom. Perhaps in some centuries hence, when every 

 corner of the globe has been examined, and multiplied experience 

 has distinguished what is true from what is false, we may be able 

 to judge more soundly of the order of nature. 



But though a true natural system has not been discovered, it can- 

 not be denied that some plants are allied by such very striking 

 resemblances, that they may be considered as belonging to natural 

 classes. Those resemblances, however, extend but to few plants, 

 and there are many wanting to connect one natural family with 

 another. These affinities, however, have been sufficient to enable 

 botanists to arrange plants by their external characters, and this 

 arrangement has been called a Natural System, (Systema natu- 

 rale.) 



Other botanists have founded their systems on the number, 

 proportion, and agreement of minute and not very obvious parts, 

 and such a system has been called Artificial, (Systema artificiale.) 



Others again select the sexual parts as the distinctive characters, 

 and found their system on the number and variety of these parts. 

 This is called the Sexual System, {Systema sexuule.) 



A System is first divided into classes and orders. In each system 

 a certain part of plants, such as the flower, the fruit, &c. is assumed 

 as the foundation, and upon that, classes, orders, and genera are 

 constructed. When a particular investigated character is common 

 to many plants, these plants make a Class, (classis). Should some 

 of the plants, beside the particular character of the class, agree in 

 another character, these form an Order, fordo). And if a few of 

 the plants, which already agree in two of the characters, are found 

 to possess others in common, these are called a Genus. Each of 

 the plants in this last division is called a Species. It is necessary 

 in a species that it remain always the same from seed. A Variety, 

 (varietas ) is a species that differs only in colour, size, or in some 

 accidental circumstance. From the seed the variety changes at last 

 into the true species. 



From a good system we expect that the part selected, according 

 to which the classes, orders, and genera are framed, shall be easily 

 seen, and without difficulty found; and that it shall be common to 

 all plants, and not subject to variation. Besides, no system ought 

 to be divided according to aiiy other character than that first 



