高校生物の教科書では，限られた植物しか組織観察の実習に用いられていない。葉の場合，硬い細胞壁をもったツバキやヒイラギがほとんどである。本研究では，数種の植物の軟らかい葉や花弁が組織実習に使用できるかを検討した。その結果，サンシキスミレ，ヤエムグラといった草本植物の葉でも徒手切片法により組織観察に十分な薄切切片が作成できた。サンシキスミレの場合，柵状組織は二層で，海綿状組織は球形でなく不定形であった。細胞壁はツバキに比べて薄かった。ヤエムグラは柵状組織が一層であった。サンシキスミレの花弁も薄切でき，向軸側の着色した円錐形の表面細胞や，無色の柔組織，維管束が観察できた。また，スイセンの花被片や副花冠の組織も観察できた。このように，多様な柔らかい葉も組織実習に利用でき，今後，葉の発生に伴う組織の変化など広範な組織実習が可能と思われる。A few plants, such as the Camellia, are used to observe the leaf tissues in the science class of the high school. Because the cells in the leaf of the Camellia have thick cell walls, it is easy to prepare thin sections from the leaf with a razor blade by hand. In this report, the leaves and flowers of other herb plants were used to observe the tissue structure. Soft leaves were inserted into the stem of the broccoli, then the leaves were sliced into thin sections. Using both leaves of Viola Tricolor and Galium Spurium, the sections could be prepared to observe the parenchymal tissues. Basic structures, such as the upper epidermis, the palisade tissue, the spongy tissue and the lower epidermis, were similar to the leaves of the camellia, but the cell shape of both palisade and spongy tissues were different from those of the camellia. Furthermore, the petals of Viola Tricolor and Narcissus Tazetta could be prepared the thin sections for observations. Thus, the present experiment was good for the histological observations of the soft leaves in the herb plants