The morphology of the air-dried seed coat mucilage.

<p>A-B. <i>Arabidopsis thaliana</i>. A. Characteristic mucilage sheets (arrow) spread between the seed and substratum (glass); B. The mucilage surface at higher magnification with the visible cellulose threads (arrows) running parallel; C-D. <i>Lepidium sativum</i>. C. Seed attached with mucilage to the substratum; D. Smooth surface of mucilage envelope. E-H. <i>Ocimum basilicum</i>. E. Seed with the mucilage envelope; F. The mucilage surface with cellulose threads (arrows); G-H. Starch grains visible under mucilage envelope; I-L. <i>Salvia sclarea</i>. I. Seed with mucilage envelope; J. Visible fragment of mucilage envelope with wavy cellulose threads (arrows); K. Broken fragment of mucilage envelope; L. Magnification of K (box) showing the broken cellulose threads (arrows) imbed in the mucilage; M-N. <i>Artemisia annua</i>. M. A very delicate mucilage around the seed; N. Cellulose threads (arrows) running parallel or in different directions within the mucilage; O-P. <i>Artemisia leucodes</i>. Abundant mucilage envelope around the seed with visible cellulose threads (arrows); <b>Abbreviations</b>: ct–cellulose threads, mue–mucilage envelope, sg–starch grains <b>Scale bars:</b> A—200 μm, F, M– 500 μm, C, E, I, O– 1 mm, D, K– 10 μm, B, F– 500 nm, G– 20 μm, H– 5 μm, J– 50 μm, L– 2 μm, N—30 μm, P– 1 μm.