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T RITICUM timopheevi Zhuk. is a species native to southern Russia and was introduced into this country by the U. S. Dept. of Agriculture in 1930. It is an unusual wheat because of its resistance to a number of diseases and because species crosses with it are highly sterile. It has proved highly resistant to leaf rust and stem rust under field conditions for the past 9 years at Madison, Wis. Several tests during this period indicate that it is resistant to bunt and mildew. It offers a new source of disease resistance which should be very valuable to the plant breeder if transferred to the common wheats. Rust resistance factors from other 14-chromosome wheats have been valuable in recently produced varieties of common wheat. Iumillo durum was the source of rust resistance in Thatcher and Y aroslav emmer for that in Hope which, in turn, has been used extensively in breeding new varieties. Investigations of Kihara and Lilienfeld 3 and of Kostoff 4 have shown that hybrids between T. timopheevi and other Triticum species are highly self-sterile regardless of chromosome number of the species used. From the cross T. vulgare Vill. variety Steinwedel X T. timopheevi, Pridham& obtained lines that were resistant to stem rust and leaf rust and T. vulgare in type.This paper briefly gives the history of a hybrid, its fertile progeny; and a few preliminary karyological observations. Crosses were made between Triticum timopheevi and a number of varieties of T. vulgare, the haploid chromosome numbers being 14 and 21, respectively. Difficulty was experienced in obtaining germinable hybrid seed when T. timopheevi was used as the female. The kernels developed to a normal size at the milk stage, but at maturity they were very shrivelled and most of them failed to germinate. There was no difficulty, however, in obtaining seed when T. vulgare was used as the female. The hybrid caryopses were smaller than normal for the female parent but were relatively plump with a visible and viable embryo. The first generation plants were highly self-sterile in all crosses. Thus, approximately 6,6oo selfed flowers from F 1 plants of all crosses have produced only 23 kernels, or 0.348% fertility. The anthers dehisced poorly and the iodine test showed about 95% of the pollen grains apparently sterile. Emasculating the F 1 plants and pollinating with T. vulgare

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CHIBNKALL has published (2) a method for extracting separately the vacuolar sap and cytoplasmic fluid in plant cells. It appeared that this procedure might be useful for chemical examination of plant tissues in relation to winter hardiness. The writers were particularly interested in a comparison of the distribution of soluble forms of nitrogen compounds and sugars between the sap and cytoplasmic fluids with the progress of cold weather. Plant materialA cold resistant variety of wheat was used, varying its resistance by change in the date of sowing. This was Wisconsin Pedigree 2, a strain of the Turkey Red variety. Alfalfa plants were secured from field sowings one year old. A range of hardiness was covered including Grimm as the typically hardy variety, Utah as semi-hardy and Peruvian as non-hardy. Agronomists recognize that winter hardiness of wheat becomes localized in the crown, or base of the stems. In the present investigation the roots were severed and the tissue below the base of the lowest leaf blade taken for analysis. Obviously, this is likely to involve considerable proportions of tissue of lesser pertinence to the investigation, but practical considerations as to the quantity of tissue rendered the grosser sampling necessary. In alfalfa the crown tissue is more limited and less definitely defined than with wheat.Hence, for the present purpose, a top portion of the tap root about 10 inches in length was taken. This was divided into upper and lower sections of about equal length. When the soil became deeply frozen it was necessary to blast, allowing the fragments to thaw at room temperature over night for recovering the plants. It must be admitted that the time elapsed in recovering tissue in this manner might permit considerable changes to occur in its composition. In the earlier samplings of wheat it was found possible to loosen the crowns quickly by playing tepid water over the soil blocks, but the heater available lacked sufficient capacity.