or priniiti\'e t\pe of xarious lamilics, and cspecialK' of groups 

 of families or orders. 



We see how comparati\el\' primiti\'e forms of plants and 

 animals ha\e persisted through geological ages alongside with 

 the evolution of higher groups. We may well believe that also 

 in the flowering plants primiti\'e forms persist in the various 

 groups. Impr()\"ed knowledge of fossils, of deveU^pment, of 

 comparative morphology of related families, will establish 

 these forms; from the present diversit\' of opinion true ideas as 

 to the actual course of plant evolution will doubtless gradually 

 emerge. 



Brooklyn Botanic Garden 



Revision of the Genus Crocidium* 



Harold St. John 



Among the many unique and interesting plants discovered 

 in Northwest America by David Douglas, was a little yellow 

 annual Composite. He found it near Fort Vancouver, now 

 Vancouver, W'ashington, on the Columbia River. From there 

 upstream for a hundred miles it is one of the commonest early 

 spring flowers. Though the individual plants are small and 

 few flowered, it grows in such abundance on the sandy flats 

 near the river as to change their color from the pale yellow of 

 the sands to the rich golden ^^ellow of the flowers. Sir. W. J. 

 Hooker described this plant as a new genus and species, 

 Crocidium midticaule during the very year of the tragic death 

 of Douglas in the Hawaian Islands. Since its publication in 

 1834, Crocidium has remained a monotypic genus. 



The first hint that there might be more than one species 

 involved came while making some dissections for drawings. 

 A study of both fresh and dried material available soon added 

 evidence. The writer then asked the loan of material from other 

 herbaria, and here wishes to gratefully acknowledge this cour- 

 tesy and assistance from the curators of the following herbaria. 

 The abbreviations listed are used in the citation of specimens to 

 indicate the herbarium in which they can be found. 



* Contribution from the Botany Department of the State College of 

 Washington, No. 14. 



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