22 INTRODUCTION. 



other plants. Those who aclo23t this view make no attempt 

 at proof. As has been already remarked, the assumption of 

 hybridity in difficult cases seems merely a mode of escape 

 from, not the removal of, a difficulty. It is often nothing 

 more than the concealment of ignorance under a bold 

 exterior. I believe in the distinctness of species, although 

 unable to demonstrate it. The great length of time requi- 

 site for experimental proof, the only kind which could result 

 in a real demonstration, renders the absolute determination 

 of this problem nearly impossible. Perhaps the most extreme 

 instance of the attempt to explain everything by hybridity 

 will be found in the Reform Deutsclier Bromheeren of Otto 

 Kuntze (Leipzig, 1867), where all the recorded German bram- 

 bles are reduced to R. fruticosus L. ( = plicatus, affinisj and 

 nitidus, of W. and N., and corylifolius of Hayne), R. candi- 

 cans Weihe ( = fruticosus W. and N., and thyrsoideus Wimm. 

 in part), R. sanctus Schreber ( = discolor^ villicaulis, carpini- 

 folius, and Schlechtendalii of W. and N.), R. Idceus L., R. 

 ccesius L., R. Radula Weihe, R. hyhridus { = pygmceus, glan- 

 dulosus, KoeJderiy Hystrix, humifusus, rosaceus, and a host of 

 others), R. saxatilis, and R. Chammmorus. In addition there 

 are 23 supposed hybrid plants: but in many cases the suppo- 

 sition seems to me to be very rash, for in this country the sup- 

 posed parents have not been observed growing in company. 



Dr Lejeune and also M. Alexis Jordan have cultivated 

 brambles extensively and raised them from seeds. They find 

 that the character of the species continues constant even after 

 repeated sowings. The Abbe Chaboisseau justly remarks 

 that it would require a century or more to be spent in 

 experiments by cultivation from seed to attain to any certain 

 result. He adds: 'L'habitant des grandes villes, condamn6 

 k etudier beaucoup plus en herbier que sur le nature vivante, 



