爵床葉部與花萼之石胞的發育

The Development of Lithocysts in the Leaves and Sepals of Justicia procumbens L.

爵床（Justicia procumbens）葉部與花萼發育過程中，石胞、毛茸與氣孔的形成均顯示有一規則性的分布型式。葉片向軸面石胞之密度與長度均較背軸面者為大，並且在葉片中央及基部之石胞的密度與長度亦較大；然而隨著葉部的發育，石胞的密度在初期增加但後期則明顯減少。接近中肋與支脈之石胞的主軸與葉脈平行，其他部位則與葉緣平行或與葉脈呈歪斜分布，石胞的排列可顯示石胞延長與葉部發育的關係。在花萼石胞只形成於背軸面表皮中，並且其主軸均平行於花萼的中肋。隨著花萼的發育，石胞的密度與長度均明顯增加，並且花萼之石胞的密度較葉部者為大。

During the development of the leaves and sepals of Justicia procumbens, the formations of lithocysts, trichomes, and diacytic stomata in both adaxial and abaxial epidermises exhibited the regular distribution patterns. The means of densities and lengths of the lithocysts in the leaves were higher and larger in the adaxial epidermis than in the abaxial epidermis, in the central area than the marginal area, and in the basal area than the leaf apex respectively. The mean densities of lithocysts increased during the early developmental stages of leaf, but in the later stages, because the enlargement of the lithocysts and the neighboring ordinary cells, they decreased obviously. The lithocysts associated with the midrib and the primary or secondary veins of the leaf were elongated along the vein axis. Elsewhere in the leaf, the axes of the lithocysts were parallel to the leaf margin or oblique relative to the midrib and showed a correlation between the leaf development and the lithocyst elongation. In the sepals the lithocysts were found only in the abaxial epidermis. They were all parallel to the midrib. The mean densities and lengths of lithocysts were higher and larger in the older sepals than those in the younger sepals. On the other hand, the densities of lithocysts in the sepal were higher than those in the leaves.