began to plant pear trees that were then seen in the catalogs. I never found a pear, among the 40 or more varieties I tried that would endure the coldest winters we had there, and if they did, I never found one that wouldn't blight. The Flemish Beauty, of all other pears, stood it the longest against the severity of the winters. But they are quite subject to blight. At Dubuque, there was originated by Mr. Longworth a pear to which he gave his name. While it is not a very good pear, yet the tree has proven to be the hardiest of all known pears that have ever gone into cultivation, and it is generally free from blight, almost wholly on the prairie soils, where I live, and there is where the pear is tested, as to breeding qualities and hardiness. On strong clay lands the pear does much better.

It was my good fortune. following the severe winters of 1883 and 1884. to have my attention called to a tree growing in Grundy county, a Chinese Sand Pear. You can see here. as I hold it in my hand, the perfectness of the wood. This tree has gone through 35 and possibly as high as 40 below, and it has always been absolutely perfect in the wood. The pear that it produces is a very small, wild pear from China, and a very promising thing to work with. The tree has not blighted and endures all the winters. So I set out in the prairie orchard a group of trees consisting of this Longworth and the Anjou, and began planting by selection the seeds that we would naturally cross in that small group of trees, and I have here about 20 or more seedling trees from that cross work, and some of them no doubt have the characteristics of these trees that have stood a temperature of 33 degrees below zero, and they are perfect, at least, there never has been but one tree of the entire number that has blighted.

I have also seedlings crossed with the Anjou and the Orel, imported by this society through Professor Budd, 30 or more years ago. That tree is not only hardy, but it is practically free from blight enduring against varieties that have been topworked on it.

Now, to show you the necessity of this work, I want to show you a Kieffer that is so deadened that it couldn't bear. I have here among these a Kieffer topworked on this very hardy seedling I have in my hand. You would be surprised to see the difference between the Kieffer itself and this limb. This limb has borne loaded to breaking down, while the Kieffer is dead on account of climatic conditions. Yet, the significance of this work lies in the fact of breeding from parentage that not only endures the winters, but is resistant to blight.

Now, when you consider that we have Wisconsin, Minnesota, the Dakotas and three-quarters of the state of Iowa, a portion of Northern Illinois and Nebraska, we have a territory five times the area of New York in which pears will never be grown, only through just such breeding work as this, and I believe from what I have seen, that it is thoroughly practical to breed away from the blight as well as to breed hardiness.

I have here in my hand a piece of wood that is almost entirely sound, the tree from which it comes has borne an enormous crop this last year,

and it bore a good crop last year, and two years ago it bore a breaking crop, the same as this year. Here is a failure in the breeding work that I never took in the full meaning of until this current year. This tree I am just speaking of, the Warner pear, is growing on the top here. You can scarcely see in the photo here where it is united. I do not think we could determine where they are joined, they have grown so smoothly. I obtained this year of our President, Mr. Graham, a number of years ago. I have two trees of that planted out on their own stem and soon after I topworked them on this Orel. There are two limbs growing on that tree, and then those trees on their own stem were so killed and rotted, by the severity of the winters that they never bore a pear and never blossomed, while those grafted on the top of the Russian Orel have produced the results stated. There is a reason for it; there must have been some change wrought in those two varieties that produced these results, and if this hardy Russian stock could so affect the top of this tree that couldn't endure on its own stem, is there any reason why it is not affecting the germs of the seeds of the pears that have grown on the top of that tree. This is a matter for us to consider in selecting seeds from trees that have shown such characteristics as these, in the advancement of this breeding work.

I might say that the Sheldon graft, topworked at the same time upon this Russian Orel, is growing as perfectly on the top of that tree seven or eight feet high, as the Warner is. So that it would seem to indicate that the other pears like the Winter Nellis I have grafted on this stock, is worth alone producing.

I think I need not say to you, after these long years, that I am very much interested in the development of the pear. So far as I have been able to see, there has been no real effort made in the United States to breed hardiness and resistance to blight, as is done at Charles City. The Government experts who have been there recognize this fact.

The President: You may now continue the discussion of this subject.

Mr. Felter: I want to ask about the Omaha plum that was introduced by Mr. Williams.

Mr. Van Houten: I do not know it.

Mr. Beebe: I would like to ask if any one here has had experience with the Sudduth pear?

The President: I had considerable experience with it. I planted 30 trees about 30 years ago, which finally bore abundantly. But soon after they weakened, and the first hard winter finished them.

Mr. Wragg: I got a lot of them from Mr. Augustine, the originator, but they all turned out to be Burketts.

pear trees.

Mr. Blodgett I never saw any particular blight about them; never anything but leaves, not a fruit or blossom.

Mr. Patten: I think I should have said in connection with my remarks as to the non-blighting character of these trees, that I learned from Col. Brackett recently while in Washington, that he had a pear tree on his place 60 years old which has never blighted; that it bore a good sized and most excellent pear. So, we have there another tree in that part of the state that has never blighted.

The President: The next paper on the program is Hybrids," by Prof. J. N. Martin, Ames.

"Graft

GRAFT HYBRIDS FROM A CYTOLOGICAL POINT OF VIEW.

J. N. MARTIN, AMES.

The subject of graft hybrids has been discussed among biologists for more than three-quarters of a century and yet even their existence has not been established. During the last decade Winkler has stirred the question anew with his so-called graft hybrids between the Nightshade (Solanum nigrum) and the tomato (Lycopersicum esculentum), and has stimulated such men as Strasburger, Baur, Beijerink and others to give the subject some attention. The subject is attractive because it has to do with the question of how character-determining factors are transmitted. It is generally believed by biologists and the belief is backed by evidence, that these factors exist only within the nucleus and that the only way to transmit them is to transmit the neucles. This means that hybrids must be obtained through the process of nuclear fusion such as occurs in fertilization. Now if hybrids can be gotten through grafting then one of two things must be true: either the character-determining factors are not limited to the nucleus, but are present in the cytoplasm as well, and are able to pass through the connecting strands of cytoplasm from the cells of one member of the graft into the cells of the other; or nuclear fusion must take place between the cells of the stock and scion. If these factors can pass from cell to cell, then scion and stock may become hybrids. If nuclear fusion is necessary, then the hybrid must arise as an adventitious branch from the wound callus.

It is quite evident in some cases, that substances do pass from the cells of one member into those of the other and produce modifications, but so far as proven this transmission is only immediate and does not affect the germ plasm. So long as there is no change in the category of the