786 LECTURE XLIV. 



' These facts, so interesting scientifically, have at the same time considerable 

 practical importance, as is seen from what follows : — 



' Experiments have shown me that (apart from V. labrusca, V. Lincecumii and 

 V. candicans) all the species named above absolutely resist the Phylloxera, and that the 

 resistance of the hybrids depends upon their composition : for example, a hybrid of 

 V. riparia and V. rupestris is capable of absolutely withstanding the insect, whereas 

 a hybrid of V. riparia and V. labrusca (' Clinton,' ' Taylor '), or of V. aestivalis or 

 V. cinerea and V. vinifera (' Jacquez,' ' Cunningham,' ' Rulander ') possesses a 

 diminished, or insufficient, resistance to the insect which no variety of V. vinifera 

 withstands. 



' Another fact well worth attention is the following : — All the species of United 

 States Vines (except V. californica and V. arizonicd) are adapted to a climate which 

 is much wetter than the wettest that is to be found in Europe ; they are consequently 

 much more resistent against all attacks of Fungi — Oidium, ' Anthracose,' Mildew 

 {Peronospora viticold) — than our European varieties of Vitis vinifera. It is found 

 moreover that those species which are most resistent against these evils are at the same 

 time those which thoroughly withstand the Phylloxera (F. riparia, V. rupestris, 

 V. cordifolia, V. cinerea, &c.). 



' Starting from this experience I (Millardet) was the first to make the suggestion 

 to employ the hybridisation of our European Vine (F. vinifera) with various 

 American ones, as a protection both against the Phylloxera and the fungoid diseases 

 referred to. All these hybrids withstand to a certain extent both the Phylloxera and 

 the injurious Fungi. It only becomes a matter of seeking out the best and most 

 resistent ones. Only by this means will the Vine-culture again become possible in 

 districts with a damp summer climate, where the Peronospora viticola makes its 

 ravages, as in the valleys of the Garonne, the west coast of Portugal, and in various 

 places in Italy, Algeria, and Switzerland. The numerous investigations in this 

 direction which I have made for two and a half years establish provisionally that it is 

 possible to confer upon our Vineyards the power of withstanding all the above evils, 

 even Phylloxera not excepted. I now possess more than two hundred new hybrids 

 which afford conclusive evidence of this. 



' It yet remains to be seen however what will be the quality of the fruit ; but even 

 in this direction I have great hopes of attaining a satisfactory result, thanks to the 

 localisation of the hybrid characters in the case of the Vine. I am convinced, for 

 example, that among a certain number of hybrids of ' Chasselas ' and Vitis riparia an 

 individual may be found with fruits like that of ' Chasselas,' with leaves like those of 

 V. riparia (resistent to Fungi) and with roots resembling those of the latter species 

 (withstanding Phylloxera). Analogous cases into which I cannot here go sufficiently 

 authorise me to make this assumption. 



' To sum up, my investigations now warrant me in making two statements : — 



(i) All varieties of the European Vine are capable of hybridisation with all the 

 American species of Vitis without exception. The complexity of these inter-crossings 

 may probably be very great, since it is just as easy to produce quaternary as binary 

 hybrids. 



(2) Even from the first generation onwards it is possible to obtain hybrids which 

 are endowed with great power of resisting Phylloxera and Fungi ' (Millardet). 



