Sein,. Observations on the Genus Rubus. 173 



137) and insularis (page 139) are in the same manner confined to the north 

 west of Skåne. R. thyrsoideus, var. subvelutinus (page löO) is only to be 

 fonnd in one place in the east of S weden, and near to this place R. thyrsoi- 

 deus g-rows. R. relatus (page 155) is only to be inet with in one sing'le 

 spot, in the east of Sweden, and R. fruticosus which otherwise is rather rare 

 in tluu district, grows not far off. R. nitidus, var. grandifolius (page 162) is 

 to be inet with only in one place, in a wood in the north west of Skåne, and 

 in the same wood grows R. nitidus which is very rare in Swedeu. This is 

 also the case with K. villicaulis and its variety alienus (page 14:!), both of 

 which are only to be found within a small area, in the south west of Norway. 

 Not less worthy of remark is the circumstance, that the parent species never, 

 as far as I know, grow together with the forms which they have produced. 



R. insularis, *confinis and its variety norvegiens (page 14.".), on the 

 contra ry. grow in districts where the parent species is completely wanting. 

 R. insularis is confined to the north west of Skåne, while R. confinis is 

 only to be fonnd in Bohuslän, and its variety norvegicus only in the south 

 of Norway. K. scanicus (page 131) is to be found in the north west of 

 Skåne and is wanting outside the boundaries of this country, but lt. Arrhenii 

 which I pre8ume to have produced this species, doe-s not grow at all on the 

 Scandinavian peninsula. I think therefore, that the two above named parent 

 species under the influence of outward circumstances could not keep unchanged, 

 but completely |i:issod över into the new forms. 



The species that show little or no inclination to produce any moie con- 

 stant varieties, are partly the herbaeeous brambles (page 44 — 47), partly R. 

 idseu- (page 168) and R. suberectus (page 10.')), which are all. really, 

 tbe oldest brambles in Europé. Ainong these species, probably R. saxatilis 

 and idfeus are preglacial, R. areticus, also R. Chama?morus, have probably 

 iramigrated to our part of the World, froiu the north of Asia (page 24) towards 

 the end of the ice-age. R. suberectus (pages 13 and 26) also is most likely 

 one of tln- oldesl black-fiuited brambles, althougb no data can be given that can 

 ald in the setrlement of the question, whether this species immigrated from 

 Asia before or alter the ice-age. Though in Europé it has produced directly 

 or indirectly all the other species belonging to Suberecti, it is very limited 

 which can h^ explained by its great age. In regard to R. saxatilis, it must 



not I verlooked, that it has produced a form, R. Areschougii, which, 



however, seems to he only occasional (page 107) and not very constant. 



