2) The culm of numerous plants of this F₄ gen. were shorter than those of wheat parent. In some progenies the tallest plant was not so tall as the shortest plant of the wheat parent, without regard to the pubescence. In some of these progenies with single short plants nearly all of them were very vigorous, with a firm culm, great tillering and a high degree of fertility. Although the culm length in the non-hairy necked plants was significantly greater than in the hairy-necked group, it may be concluded that the shortening of the culm was not merely connected with the presence of I rye chromosome or part of it, because there were some true-bred non-hairy necked progenies in which all plants were shorter than the shortest variant of the wheat parent.

3) Numerous plants of this F₄ gen. had a thicker culm than the mother parent without regard to the "hairy neck" or "smooth neck" character respectively.

4) There was significant correlation between the number of kernels per ear and the "smooth neck" character. It may be pointed out that an addition of a I rye chromosome to the wheat genome caused lower fertility of the plants with the pubescens pendicule. There were numerous positive transgressive variants in comparison with the wheat parent. This effect may be attributed to the expressiveness of the cumulative factors for yield of both parents.

5) There was a great correlation between the fertility per spikelet and "smooth neck" and for this character the same can be concluded as for the total number of kernels per ear.

6) Plants with a "smooth neck" had a higher "total weight of kernels per ear" than those with the hairy neck character. This difference is significant. A few plants (2.2%) were positive transgressive in comparison with the wheat parent.

7) The difference in the 1,000 kernel weight between plants with a "smooth neck" and those with a "hairy neck" is not significant. From these results it may be inferred that presence of the I rye chromosome in the genome does not cause depresion in the development of the kernels. This effect may be attributed to the negative action of another rye chromosome or part of it in the genome or to the action of cytoplasmatical factors.

8) The difference in shape between kernels of plants with a "smooth neck" and kernels of plants with a "hairy neck" is significant, but it is not total because there are in both groups some plants with long kernels and others with more round kernels.

The cytological investigation of this hybrid will be published separately.

(Received Oct. 15, 1957)