150 F. W. C. Areschoug. 



of its identity with the contiaental forras cannot arise. Also, I have seen forms 

 from England, which nearly accord with ours; though on the other hand, many 

 forras in England and southern Europé, analogous to R. thyrsoideus, are 

 considered as this species. 



For my part, I do not entertain any doubt, that this species originates 

 from R. corylifolius, viz, from the subspecies * nemoralis. The poorer, and 

 the more vigorous forms of R. thyrsoideus, answer pretty nearly to both the 

 subspecies, * nemoralis (particularly its variety acuminatus), and * Wahl- 

 bergii, of R. corylifolius. Especially worthy of notice is the resemblance of 

 the inflorescence, between the poorer form of R. thyrsoideus and the northern 

 form of R. * nemoralis, var. acuminatus, from Dalsland, also growing in 

 sterile träets, and which 1 have previously raentioned (pag. 52). The petals in both 

 these species, likewise varv inform. R. thyrsoideus, however, from the whole of 

 its exteriör organisation, is more fitted to live in a warm climate, than our 

 R. corylifolius. In this country therefore, it does not go so far towards the 

 north, nor so far inland, as the last named species. It also belongs, in a 

 gieater degree than R. corylifolius, to warm, sunny and stony slopes in 

 mountain tracts. On the other hand, it is much more common on the east 

 coast of the Scandinavian peninsula, than on the west; as also, it is more 

 common in the eastern part of Germany, than in the West. Focke (Syn. Rub. 

 Genn. page 169) also states that he has seen specimens from Hungary, 

 Slavonia, and Bosnia. In consequence of this, I think that it is very likely, 

 that U. thyrsoideus arose in mountainous tracts, in the south east of Europé, 

 out of some eglandulous form of R. corylifolius, * nemoralis. 



Lindeberg (Horb. Rub. Scand. n. 10) has distinguished, and described a 

 variety of this species, which he calls subvelutinus. It is distinguished by 

 the following characteristics. 



var. subvelutinus Lindeb. (1. c); turionibus alte arcuatis vel suberectis, 

 apice nuiantibus; foliis mollibus, subtus velutino-canescentibus, foliolis angusti- 

 oiil.us, longius acuminaiis & acutius serratis; petalis semper albis, longius & 

 angU8tius unguiculatis, glabrescentibus; filamentis albis, stylos virescentes aequan- 

 tibus; receptaculo sparse piloso. 



This particularly interesting variety grows in the eastern part of Bleking, 

 near Karlskrona, in a thin oakwood, on rather dry ground at Boråkra. 



Focke, to whom 1 have sent specimens of this variety, thinks it approacb.es 

 R. candicans Whe. In spite of the cireumstance, that both the species, into 



