抄録
The first leaf of seedlings in cereals shows two different modes of folding i. e. right- and left-handed (cf. Diagram 1). The present paper deals with the statistics of such R- and L-grains on the ear in two-rowed barley. Results obtained are summed up as follows:
1. There are three regular type ears with regard to the numbers of R- and L-grains in odd and even row of the ear;
a) parallel or P-type RO/LO:RE/LE=n/m:n/m
b) cross or C-type _??_=n/m:m/n
c) equal or PC-type _??_=m/m:m/m
The others, however, show some irregularities in the numbers of R- and L-grains in each row of the ear, such as y/x:w/z. But these irregular type ears may be shifted to the regular ones, if we adjust one or more grains in each row from R to L or vice versa. Hence we may have several kinds of modified P-, C- and PC-types (e. g. P1-, P2-, C1-, C2-, P1C1-, P2C2-……) according to the degrees of modifications, as being exampled in Diagram 2 and Table 2.
2. Series of the regular and modified P-, C- and PC-types obtained and their frequencies in a total of 194 standard ears are given in Table 2. It is noticeable that the parallel type ears occur more. frequently than the cross type ones, the ratio being 60.1:36.7.
3. From the results above mentioned, it may be confirmed that the numbers of R- and L-grains in odd and even row of the ear in two-rowed barley show a definite relation, indicating as RO.LO=RE.LE, althogh exceptional cases are found.
4. Both even and odd rows in the ear generally gave an excess of R- type grains, the percentage being 56.7 (Table 1).
