抄録
"Hard wheat" is sometimes erroneously understood as protein-rich wheat. Hardness of grain concerns partly with the protein content, of course, but more essentially with the character of endosperm (Table 1). The crystalloidal property was ascertained optically by the transparency of vitreous particles in the hard wheat flour, placed between crossed Nicols in the orthoscope system of a petrographic microscope. These flour particles are the fragments of endosperm, and the pieces of cytoplasmic matrix (mainly composed of protein) imbedding starch granules. It was noticed also that this property denaturated by moistening and re-drying of the grain, while its hardness decreased along with it. (Table 2) Thus, the author presume, the hard wheat will be characterized by the grain hardness due primarily to the crystalloidal property of endosperm. Such crystalloidal property was observed in certain varieties of Tr. vulgare, and in all of Tr. durum and Tr. polonicum so far as examined. This property, therefore, must be one of the heritable variation occurred in the endosperm of wheat, so much likely as the glutinous character found in other cereals.
