98 NOTES ON ENGLISH RUBI. 



of a few dried branches can lead to a real acquaintance with a 

 difficult bramble. It would be more instructive to examine the 

 living plant, but nobody can visit all localities where doubtful 

 species are growing. 



It would be tedious to enumerate all the various difficulties 

 which we cannot escape in these researches. The question arises — 

 are we obliged to waste our time in studying the foolish writings of 

 every ignorant and mischievous manufacturer of names ? A neglect 

 of such productions has nothing to do with the esteem we pay to 

 the work of our true predecessors in science. 



Several botanists have thought that knowledge would profit 

 more from a diminution of the numerous species than from an 

 increase. Therefore they combined a great number of different 

 forms, producing in this manner an aggregate species. The easiest 

 way to escape all difficulties would be to establish a Rubus pulij- 

 morphus, as Spenner did. In following his example we either 

 obstruct scientific research, or, if we admit subspecies and varieties, 

 we change the terms only. At present we are accustomed to say 

 Rubus suberectus, R. plicatus, &c, but it is a matter of mere 

 convenience if we should prefer to alter this nomenclature into 

 R. fruticosus subsp. suberectus and subsp. plicatus. Science would 

 neither be improved nor damaged by this arrangement. In other 

 groups of our brambles the question is much more intricate. 

 Certainly the limits of the separate forms are often very difficult 

 to trace ; but between the aggregate species, comprehending all 

 connecting links, exist no limits at all. 



My own opinion is that in such genera as Rubus, Rosa, Hieracium, 

 and many others, hybridization once has mixed the old species, 

 with the effect of producing, in the course of many hundred years, 

 numerous new species of a lower order. At present we see exactly 

 the same occur in the Ehododendrons, Fuchsias, Begonias, Abu- 

 tilons, and many other favourite plants of our gardens. In all the 

 second-rank species, originated in the woods or in cultivation, the 

 pollen contains a considerable number of imperfect grains. There 

 are only three English blackberries which have quite regular 

 pollen-grains, viz., R. ccesins, R. rustic-anus, and R. gratus. 



These views do not necessarily lead to the conclusion that at 

 present there must take place abundant intercrossing between all 

 our existing brambles. R. casius, R. restitus (leucostachys), and R. 

 rusticauus (on the Continent R. tomentosus and R. rudis too) are very 

 much inclined to produce hybrids as well inter se as with many 

 other species. Everywhere we observe associated with them a good 

 many perplexing intermediate forms and connecting links resisting 

 all attempts at classification. We must not fancy that hybrids are 

 always rare. On the Continent the R. ccesius x Idaus, a hybrid 

 which I have produced artificially, is in many districts a common 

 plant, although it very seldom bears a single fruit, and is usually 

 altogether sterile. Frequent hybridization, however, is not a general 

 rule among our brambles. On the contrary, hybrid brambles, 

 which are not procreated by one of the few species named above, 

 arc of rather rare occurrence. 



