352 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



given in most works dealing with it is very unsatisfactory. Generic 

 relationships appear never to have been definitely settled, and the 

 synonymy has never been completely established. 



In addition to the material in the National Herbarium the writer 

 has had the privilege, through the kindness of Dr. William Trelease, 

 of examining all that in the herbarium of the Missouri Botanical Gar- 

 den. He also wishes to express his obligations to Dr. J. M. Greenman 

 and to Prof. L. M. Umbach who have forwarded material for study. 

 In the two larger lots of material examined several sheets of various 

 species of Serinea were found. This genus can readily be distin- 

 guished from those treated here by the fact that its achenes are alto- 

 gether without pappus. 



The plants included by most of the later American authors in the 

 genus Adopogon have been described by the botanists who have stud- 

 ied the plants of the eastern United States under several generic and 

 many specific names. Linnseus described two of them in his Species 

 Plantarum under different generic names, one in the genus Trago- 

 pogon and the other in the genus Hyoseris, the latter name being 

 now applied exclusively to a European group. Schreber in 1 791 made 

 the Linnaean Hyoseris virginica the type of the new genus Krigia. In 

 1829 Don founded the genus Cynthia upon Tragopogon virginicus. 

 Since that time some authors have accepted these genera as distinct, 

 while others have merged them in Krigia or in Adopogon. 



Torreyand Gray in 1843 considered the genera Cynthia and Krigia 

 distinct. Besides this, they founded under Krigia a new section, 

 Cymbia, for the Nuttallian Krigia occidentalis. De Candolle kept the 

 two genera separate, while Bentham and Hooker united them under 

 Krigia. Doctor Gray in the Synoptical Flora followed Bentham and 

 Hooker, but very properly recognized three sections of the genus, 

 Cynthia, Eukrigia, and Cymbia. He also gave a good account of the 

 synonymy of the group, although he omitted numerous published 

 names. When Otto Kuntze published his Revisio Generum Plan- 

 tarum in 1891 he united all the species of the group under the Neck- 

 erian genus name Adopogon. In this he has been followed by Britton 

 and Brown and by Small. 



All three of Doctor Gray's sections, the writer thinks, are worthy of 

 generic recognition. The groups are very natural ones, sharply 

 defined, at least as much so as most of the genera of the Compositae. 

 The genus Cymbia here proposed is farther removed from the genera 

 Cynthia and Krigia than those two are from each other, although the 

 latter have been separated by most authors, while Cymbia has never 

 been segregated from the genus Krigia. 



Adopogon of Necker is very fully described by that author in the 

 first volume of his Elementa. He names no species, but says that 

 the genus is founded upon certain of the Linnaean Tragopogons. 



