CAUSES OF COXFl'SION IX PLANT N'AMlCS 161 



Paiiiciiiii of Linnaus contained such diverse grasses as pearl millet, 

 common millet, barnyard grass, Pasf^alitiii, St. Lucie grass (Stenota- 

 phriun) , crabgrass, Opilismenus, and Bermuda grass, besides the group 

 now called Panicuni. His Holcus contained sorghum and Johnson 

 grass, velvet grass, holy grass, or vanilla grass, a species of Uniola, and 

 one of Sacciolcpis. The generic names given to such heterogeneous 

 groups were subsequently differently applied by different authors, ac- 

 cording to which of the diverse elements they applied it. Today bot- 

 anists are striving to formulate reasonable rules to govern the choice 

 of the types of such genera, so that the generic names may be perma- 

 nently fixed. This is the most difficult problem which nomenclatorial 

 rules aim to solve. 



The second cause of the confusion in names was the relative isola- 

 tion of the different workers. A few industrious compilers like Roemer 

 and Schultes for a time sought to bring together the new genera and 

 species, ever increasing in number as the result of scientific voyages 

 and exploring expeditions. Their attempts at co-ordination sometimes 

 wrought confusion because their work was based largely on literature 

 and not on the plants. There was a short-lived Xeue Entdekungen fur 

 Pflanzenki^inde in the early nineteenth century, and a Botanischer 

 Zeitschrift later, that attempted to review current botanical literature, 

 but these could do little in so rapidly growing a field. Ignorant of each 

 other's work, men in different countries often described the same genus 

 under dift'erent names, or various authors hit upon the same w^ord in 

 naming diverse genera or in naming dift'erent species in the same genus. 

 The name Elodea, for example, was given to a common water-weed 

 and to the pretty pink-flowered ally of the St. Johnsworts ; a lichen and 

 a grass were both called Sctaria. In the third and fourth decades of 

 the last century, another industrious compiler, Steudel, prepared a 

 Xomenclator Botanicus, which, while faulty, must have been a most 

 useful work, being an index to the place of publication of plant names, 

 generic and specific. But the second (and last) edition of this was 

 issued in 1840 and 1841. It is Darwin who, impressed with the need 

 of such work, left funds for its compilation, that we have to thank for 

 the Index Kewensis. Darwin's original idea, so his son tells us in the 

 "Life and Letters," was a nomenclator simply. The plan of attempting 

 to pass upon the validity of genera and species and of referring them 

 to synonymy developed at Kew as the work proceeded. This attempt 

 to establish names by fiat for awhile added to confusion, for there was 

 a tendency when the index first appeared to accept its fiat. Most 

 middle-aged systematists today can recall the shock they sustained when 



