18 METASPERMAE OF THE MINNESOTA VALLEY. 



such as those of Pfeiffer (27), Steudel (28) and Kuntze (29) 

 together with the laws of zoological and botanical congresses 

 and papers by distinguished taxonomists, such as Agassiz and 

 A. Gray, have been freely consulted and the basis of nomencla- 

 ture in the case of the Metaspermae has been de-rived from 

 such critical, historical and bibliographic labors. Those 

 who are interested in the detail may find abundant discussion 

 in these cited works, which, together with the controversial 

 and argumentative material published from time to time by the 

 Royal Botanical Gardens at Kew, the Continental and Austra- 

 lasian Gardens and the various botanical periodicals and 

 ephemera that concern themselves with such subjects, will be 

 found to present the questions outlined above, from a wide 

 variety of view-points. With Kuntze, it may well be said that 

 while nomenclature itself is hardly to be named a science, it is 

 certainly an important adjunct of science and as such demands 

 thoughtful attention. 



Arrangement of families and genera. The arrangement of 

 families and genera follows as exactly as possible the lines laid 

 down in Engler and Prantl's Natuerlichen Pflanzenfamilien, which 

 is beyond compare the most important taxonomic summary yet 

 published for the plant-kingdom. This arrangement is. not 

 particularly different from that which has come to be generally 

 recognised within the last ten years. It is similar in general 

 outline to that of Luerssen (30), Drude (31) and Warming 

 (31^), and is a clear expression of modern views of the inter 

 relationship and evolution of the flowering-plants. Such an 

 arrangement is preferable to the more ancient ones just in such 

 degree as it is more accurate. The accuracy of the arrange- 

 ment adopted is acknowledgedly incomplete, but it is believed 

 to represent the full research of the times. 



Natural diyisions of the vegetable kingdom. The constant 

 effort of the botanist is to make his classification of plants indi- 

 cate not only resemblance but relationships. Indeed resem- 

 blances are considered of value in taxonomy only in so far as they 

 indicate relationships. For this reason no classification is, or 

 can be stable, since no classification is ever mature or com- 

 plete. The ever-progressing knowledge of plant-anatomy, dis- 

 tribution, physiology and especially of embryology renders the 



(27). Pfeiffer: Nomenciator Botanicus (1874) 1 

 (28). Steudel: Nomenciator Botanicus, ed. II. (1840-41.) 

 (29). Kuntze: Rev. Gen. (1891.) 

 (30). Luerssen: Systematischen Botan. (1878-1882). 

 (31). Drude: Syst. und Oeogr. Anordn. Phan. (1890). 

 Warming: Syst. Botan., Germ. Tran. 



