president's address. Ill 



forming some of our larger genera are due to hybridization, has 

 produced, I think, an injurious effect upon the study of the wil- 

 lows especially. Hardly any one now will be at the trouble to 

 make them out. They repel instead of attracting the botanist, 

 and the genus is regarded as a mass of shifting and unstable forms 

 defying description, or, when described, incapable of satisfactory 

 recognition. That willows vary cannot be denied, and if the 

 range of variation was once determined, we should then know 

 better than we do now what constitutes a species. Too little 

 allowance seems to have been made of late years for the influence 

 of soil, climate, exposure, and such like possible causes of change. 

 A different course, not with the happiest results, has been 

 adopted. Wheru forms occur intermediate between other forms 

 hitherto recognized as species, the difficulty is got over by the 

 ready explanation that the intermediate form is a hybrid. It is 

 entered in some book, branded with a dagger or a cross, some- 

 times further punished by the addition of two names, like the 

 spurious issue of an unlawful union, thus pointing it out to be 

 skipped by the student as a sort of botanical nonentity that may 

 or may not occur again. That hybrids may exist in nature I am 

 by no means prepared to deny; but it appears unphilosophical 

 to conclude that a plant is a hybrid, without experiment, mainly 

 because we do not exactly know what to do with it; and I think 

 a student of nature may object to be told by authority that a 

 plant is undoubtedly a hybrid, though no valid reasons are as- 

 signed. That learned and most industrious student "Wimmer, 

 in his work on the European Willows, speaks as if an eye for 

 hybrids may in time be acquired. ' ' Huic rei quum per longam 

 annorum serieni operam dedissemus effectum est tandem, ut quid 

 salicis species esset, quid non, ipsi nobis statuere posse videre- 

 mur." A mode of determination which, however cautiously 

 employed by its author, is not calculated to convince those who 

 are not already believers in the theory. For the last two years 

 I have for my own satisfaction been prosecuting such enquiries, 

 and I hope to do so on a larger scale. I wish I could induce 

 some of the members of the Tyneside Club to undertake similar 

 experiments. I have already four seedling plants raised from 



