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ANY simple test that will aid the wheat breeder in measuring 1"\. characteristics of grain is of value in increasing the efficiency of the breeding program. In the eastern soft wheat region hard wheats are being used extensively as parents to secure resistance to various diseases and a simple test is especially needed for identifying, in the early generations, hybrid lines with soft grain. Hard wheats in general produce coarse granular flour and soft wheats fine smooth flour. The particle size index test developed by Cutler and Brinson 3 appears to differentiate varieties in a very satisfactory way so far as this character is concerned. It is slow, however. The doughball time test has also been suggested by Cutler and Worzella 4 as a measure of quality for small samples. Since the degree of granulation of a flour seems to be related to hardness of the grain, it occurred to the authors that a pearler such as is used in the inspection of barley and which has also been used for studies in the milling of parboiled rice, might be useful in estimating the hardness of wheat samples. Some preliminary trials seemed to verify this assumption and hence a more extensive investigation was planned and carried out. The results appear promising enough to justify presenting the results. MATERIALS AND METHODSThe pearler consists of an enclosed grinding stone attached to a Ys h. p. directdrive electric motor. An interval timer, a balance sensitive to o.or gram, and a set of Tyler screens completes the apparatus necessary for the pearling test.Preliminary tests were made on grain of varieties grown in field plats at the Arlington Experiment Farm, Arlington, Va. Later samples from the varieties in the uniform soft winter wheat nurseries grown at several stations in the eastern states were studied. Also, in order to obtain data with a wider range of kernel types, samples of a few winter and spring varieties grown in field plats at experiment stations in the western United States were included.The wheat was stored for two months or more prior to pearling in an ordinary seed storage room. The moisture in the grain varied between ro and r 1% and no shriveled or badly broken grain was used. The procedure used in the test was as follows:1. Approximately 100 grams of wheat were placed on a No. 6 Tyler screen held over a No. 8. After shaking a definite number of times by hand, three 20gram samples were weighed from the grain remaining on the No. 8 screen.2. A sample was placed in the pearler and the latter started and run exactly 3 minutes.

T HE coordinated wheat improvement experiments at 17 stations in eight western states (3), 3 have offered an excellent opportunity for a study of the performance of awned and awnless wheats under very diverse environments. The problem is of both theoretical and practical interest. Many of the previous experiments with wheat to determine the influence of awns on yield and kernel weight have not been conclusive and no attempt has been made to test similar material at more than one location. In general, awned plants have tended to produce heavier kernels and a higher weight of grain per plant, although this has not always been the case. Clark and Quisenberry (r) and Lamb (2) have reviewed the literature on the effect of awns in wheat.The data on the effect of awns presented here were obtained from composite populations of awned and awnleted segregates from two crosses, one between two winter varieties and the other between two spring varieties. Material for another method of comparing awned and awnless wheats is being developed, but results will not be available for several years. This material is being produced by repeated backcrossing of awnless segregates with the awned parent and awned segregates with the awnless parent. It is planned to continue backcrossing until types similar to the two parents in all genetic characteristics except presence or absence of awns have been obtained. These should be better suited for further studies on the influence of awns on the development of the wheat kernel.

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