THE GENUS SYMPHYTUM IN BRITAIN 



By T. G. TuTiN 

 University College of Leicester 



The identification of S. peregrinum has caused much trouble to British botanists 

 but a re-examination of the S. officinale-peregrinum-asperum complex suggests that there 

 are in fact only two species and a hybrid swarm involved. 



The main morphological differences between the three taxa which have been commonly 

 recognised are set out in Table 1. 



Table 1. 





S, officinale 



' S. peregrinum ' 



S. asperum 



Flower colour 



Yellow-white 



Purple 



Blue 





(rarely purple) 







Calyx-teeth 



linear-subulate 



variable 



triangular 



Calyx 



not accrescent 



± accrescent 



strongly accrescent 



Leaf base 



strongly decurrent 



± decurrent 



not decurrent 



Hairs 



stiff 



variable 



almost prickly 



Anthers 



longer than filaments 



equalling filaments 



shorter than fila- 









ments 



S. officinale L. is a rather local plant of river banks and wet ditches occurring in 

 most of Europe, except the arctic, eastwards to the Caucasus, W. Siberia and Central 

 Asia. In W. Europe it most commonly has yellowish-white flowers, but purple-flowered 

 forms were recorded by Ray in the 17th Century and still earlier by Gerarde. It is 

 interesting to note that Popov (1953) does not mention the yellowish-white form at all 

 as a Russian or Asiatic plant. 



S. asperum Lepechin (S. asperrimum Donn) is native in the Caucasus but is now 

 widely naturalised in Europe though very rare in Britain. It appears to have been 

 introduced about the beginning of the 19th Century and to have been described from 

 the gatherings of M. Bieberstein, for which no precise locality was given. Donn records 

 it as having first been cultivated in the Cambridge Botanic Garden in 1801 (not 1811; 

 see English Botany) and it was grown extensively as fodder a few years later. It is pre- 

 sumably from this introduction that the hybrids arose, some of which have gone under 

 the name of ' S. peregrinum ' ; the whole hybrid swarm should in fact be known as S. X 

 uplandicum Nyman. S. X uplandicum Nyman was first described as S. patens E. M. 

 Fries (non S. patens Sibth.) in 1839 from the province of Uppland in Sweden, where it 

 must have resulted from the crossing of native S. officinale with introduced S. asperum. 

 This invalid name was later replaced by the name S. uplandicum Nyman. It should be 

 noted that the original, and presumably correct, spelling of the name is uplandicum in 

 spite of the fact that the province after which it is named is called Uppland. The hybrid 

 is also well known from the Caucasus, where the geographical areas of the parents appear 

 to overlap. 



The range of variation in the hybrid is great and plants may be found showing all 

 combinations of the characters of the parents. The fact that the parents maintain their 

 distinctness would appear to be due mainly to their ecological isolation; S. asperum is a 



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