Horsetail spores. Coloured scanning electron micrograph (SEM) of spores of a horsetail (Equisetum sp.). The spores (orange) bear elaters (green),which expand and contract with changes in humidity. Elaters help to tangle spores together into a clump called a propagule,and to dig spores into the soil. Horsetails are the only living group of a primitive family of plants,the Sphenopsids,that date back to the Devonian period,355-410 million years ago. Horsetails normally spread by asexual reproduction using rhizomes (underground stems). Magnification: x180 at 6x7cm size | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Nishinaga, Susumu |
Bildgröße: | 3583 px × 2938 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |