1876.1 



AND HORTICULTURIST. 



30t 



uniting two halves of different buds and grafting 

 them together. Thousands of people have 

 laughed at these notions. No one has tried them. 

 But only a few years ago it was found that Brad- 

 ley was right ; and we have in cultivation new 

 variegated forms of ahutilon, as well as some 

 other things originated by the graft process. 

 During the past few years it has been asserted 

 that new varieties of potatoes have originated in 

 this way : — a tuber is taken and all the eyes cut 

 out. A wedge with an eye of another kind is 

 then inserted into the eyeless mass and planted. 

 The results are said to be true hybrids. Many of 

 our best physiologists doubt this. I have not seen 

 these cases ; but I must say the evidence offered 

 is much stronger than much of that on which 

 some popular theories have been built. I tried 

 the split and grafting process, not belieWng it 

 would result in a hybridity. I merely wished to 

 test the popular notion. I am pleased to be able 

 to say now that it is correct. New varieties can 

 be obtained in that way. I took the Rhode 

 Island Greening and the Red Astrachan — two 

 very distinct varieties of apples in every respect. 

 The grafts with a single bud were split as near 

 through the centre as passible, and a piece of 

 each kind fitted together so as to appear one 

 complete scion. Twelve of these were grafted; 

 three grew ; two of these have fi-uited; neither 

 are Rhode Island Greening, and the two are un- 

 like each other; one of these has a flower like 

 the Rhode Island Greening, and the flower of the 

 Red Astrachan is rosy and in many ways distinct 

 from the large white one of the Rhode Island 

 Greening; but the fruit is, in many respects, 

 similar to that of the Red Astrachan. The sec- 

 ond variety has the flower similar to that of the 

 Rhode Island Greening, and the fruit somewhat 

 the color of the Red Astrachan, ripening about 

 the same time, but is but half the size, very 

 much flattened, and with a slender stem near two 

 inches long, and as much like that of a Siberian 

 Crab as can be. There is no doubt but two vari- 

 eties, distinct from their parents, and distinct 

 from each other, have resulted from this graft 

 process. Some may suppose that the union of a 

 Red Astrachan and a Rhode Island Greening apple 

 should result in producing an exact intermedi- 

 ate, and that the union of buds in several graft 

 cases should each produce identically the same, 

 and therefore the two distinct varieties from the 

 same process be a surprise. But no two chil- 

 dren of the same parents are exactly the same; 

 and this is the experience of plant hybridists. ' 



Our fellow-member, Mr. W. Saunders, of Lon- 

 don, Ontario, crossed the American gooseberry 

 (Ribes Cynobasti) with the red Warrington, an 

 English variety, but both with hairy fruit. The 

 hybrid product has smooth fruit, thus introdu- 

 cing a character not extant in either parent. 

 And as regards variety, I have myself, from one 

 single berry of a fertilized Fuchsia, produced sev- 

 eral score of plants, among which no two were 

 alike. I do not know that there is any pomo- 

 logical value in the new varieties of apples I 

 have raised, but I am delighted with the scien- 

 tific results, proving that hybrids by bud-graftmg 

 is more than a popular delusion. 



NOTES ON THE AMERICAN GRAPE VINE 

 MILDEW.* 



The grape vine seems to afford special induce- 

 ments for the growth of fungi; Curtis, in his 

 list, enumerating no less than eighteen species 

 which grow upon it. "The grape disease, prop- 

 erly speaking, that which proved so disastrous 

 at different times to the vines in Europe and 

 Madeira, is caused by a fungus to which Berk- 

 eley has given the name of Oidium Tuckeri." It 

 is a form of a fungus which has not yet been 

 recognized in its perfect state, and is supposed 

 to occur to some extent on this side of the water ; 

 but as many fungi have this conidial form, and 

 some so nearly identical with it, and also growing 

 on the grape, there may be some doubt as to our 

 vines ever being attacked by the true grape dis- 

 ease of Europe. 



The disease which most interests the grape 

 growers of America, is the fungus called Pero- 

 nospora viticola by Berkeley and Curtis. It is 

 quite common, appearing on the under surface 

 of the leaves about the first of August, and con- 

 tinues to flourish until the dj'ing leaf will nour- 

 ish it no longer. It can be most easily seen on 

 the smooth leaves of Vitis cordifolia, as small 

 frost-like spots, which rapidly spread, and soon 

 cover the whole leaf, frequently extending down 

 the petiole to the stem. This fungus, like the 

 potato rot and other closely related species, 

 thrives best in moist, warm weather. 



Under the microscope, the tissue of the grape 

 leaf is seen to contain an abundance of minute 



* An abstract of an article on this subject by Dr. W. G. Far- 

 low, In the last issue of the Bulletin of the Bussey Institution. 



