THE CLASSIFICATION AND NAMING OF PLANTS 6 1 



the first natural systems of classifying plants (and animals) 

 was that of Linnaeus. The first edition of his notable work, 

 Systema Naturae, was published in 1735. There follow 

 the systems of De Jussieu (1789), De Candolle (1819), 

 Eichler (1883), Bentham and Hooker (1826-1883), and Eng- 

 ler and Prantl (1890-1896). Two recent systems are those 

 of Bessey (1907), and of Schaffner (1911). 



Reproductive versus Vegetative Organs in Classification. 

 — In all higher plants, reproductive and vegetative organs 

 differ markedly from each other. Reproductive tissues are 

 less influenced by environmental conditions than are vege- 

 tative tissues. There may be little resemblance between 

 the vegetative portions of two species, although their repro- 

 ductive structures may be very similar. For example, the 

 strawberry and raspberry have quite different growth form, 

 and their vegetative organs are quite dissimilar, yet the 

 flowers of the two are constructed on the same general plan. 

 On the other hand, two plants with very dissimilar reproduc- 

 tive structures, i.e., having little natural relationship, may 

 resemble each other very closely in their general vegetative 

 appearance. These conditions show that, although vege- 

 tative structures may be modified to a great degree under 

 diverse environmental influences, these same influences do 

 not modify, to an equal extent, the reproductive organs. 

 Hence, on account of this greater stability of the reproduc- 

 tive structures of a plant, these are of relatively great value 

 in showing actual relationships, and are of prime importance 

 in classification. 



GROUPS OF PLANTS 



A survey of the plant kingdom shows it to be composed of 

 a great variety of plants, differing in size, in structure, in 

 habitat, and in method of living. 



