Vol. 7. No. 8. 



TORREYA L.BRARV 



NEW YORK 



August, 1907 BOTANICAL 



GARDEN 



THE GENUS PILOSELLA IN NORTH AMERICA 



By p. a. Rydberg 



PILOSELLA (Thai) Kostel. Enum. Hort. Prag. 104. 1844. 

 Arabidopsis (DC.) Schur. Enum. PI. Trans. 55. 1866. 

 Stenophragma Celak. [Fl. Prager Umgeg. 1870] Flora 55: 

 438. 1872. 



Prantl in Engler & Prantl, Pflanzenfamilien, adopted Cela- 

 kowsky's genus Stenophragma for Arabis Thaliana L. and its 

 relatives. There are, however, two older generic name.s avail- 

 able. Neither of these has been included in Harms's list oi genera 

 excludenda and they must be considered, whether one follows the 

 American or the Vienna Code. The first of these was published 

 by Kosteletsky in 1844. Kosteletsky not only gives the bino- 

 mial Pilosella Thaliana but states in a footnote that it has been 

 included in Arabis and Sisymbrium by authors. Furthermore, he 

 credits the name Pilosella to Thai, by placing the name of the 

 latter in parenthesis after the name Pilosella. Pilosella siliqnata 

 minor was described and figured by Thai in 1588 and it was the 

 plant on which Linnaeus based his Arabis Thaliana. There is 

 therefore no uncertainty about the identity of Kosteletsky's genus 

 Pilosella. Some botanists require that a diagnosis (some even 

 insist that this should be in Latin) should accompany a generic 

 name in order to constitute publication, but such a requirement is 

 always at least pedantic and in many cases simply ridiculous. 

 In this case the identity of the genus Pilosella (then a monotype) 

 is well established, and the plant was described and figured by 

 Thai and described by Linnaeus. 



It is true that the name Pilosella has been used for a part of 



genus Hieraciinn, but according to the American and the Vienna 



[No. 7, Vol. 7, of ToRREYA, Comprising pages 133-156, was issued July 19, 1907.] 



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