Studies in Sisyrinchium— VIII : Sisyrinchium Californicum and 



Related Species of the Neglected Genus Hydastylus 



By Eugene P. Bicknell 



The well-known Sisyrinchium Californicum of Alton's Hortus 

 Kewensis has rested for so long undisturbed in the genus Sisy- 

 rinchium that some fault of iconoclasm would seem to attend 

 its removal from its time-honored place. Nevertheless the gen- 

 eric misfit of the plant in Sisyrinchium was long ago appre- 

 hended and a separate genus was created for it by Salisbury on 

 the suggestion of Dryander (Trans. Hort Soc. i: 310. 18 12). 

 This genus, Hydastylus, adequately founded as I do not doubt, 

 appears to have missed the sanction of any later systematist. 



The species was first brought to notice by Archibald Menzies 

 who imported it into England for cultivation in 1796. Ten years 

 later it was described and figured by Ker-Gawl as Mark a Call- 

 f arnica (Bot. Mag. t 983, 180 ?), a disposition of the plant mani- 

 festly having regard for family relationship rather than generic 

 affinity. 



In 18 1 2 Aiton, or Dryander, it may be, with clearer view 

 transferred it to Sisyrinchium. The same year Dryander and 

 Salisbury reached a truer conception of the plant's separateness of 

 structure from Sisyrinchium, and their genus Hydastylus must 

 now be revived to accommodate not this plant alone but also a 

 well-defined generic group of yellow-flowered species of which it 

 is the type. 



The genus Hydastylus may be thus characterized : 



Annual or perennial herbs with the habit and appearance of 

 Sisyrinchium, but usually only imperfectly caespitose, discoloring 

 or turning black in drying, most or all of the species staining pur- 

 ple under appropriate conditions ; rootstocks usually obscure or 

 poorly developed, the delicate roots pale and slender. Leaves nar- 

 rowly linear, the conduplicate bases more or less membranously ex- 

 panded : stems ancipital, simple and scapose, terminated by a spathe 

 of two conduplicate bracts enclosing membranous scales ; pedicels 

 slender, often long-exserted, straight or finally recurved : perianth 

 yellow, the mostly narrowed segments black-lineate or with brown 



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