Light micrograph of the colonial hydroid Obelia sp. ,showing pairs of blastozooid and feeding polyps attached to a central stolon (red stalk). The stolon net covers large areas of stones,seaweed,buoys and flotsam,sending out tiny branches perpendicularly,up to 4cm in length. Obelia (order Thecaphora-Leptomedusae),posseses a flask-like envelope into which the polyp heads can retract. A division of labour exists in the colony: the blastozooid polyps (no tentacles) containing medusal buds are concerned with reproduction,whilst the ones with tentacles take in food. Magnification: x25 at 35mm size | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Kocher, Dr. Clive |
Bildgröße: | 3085 px × 3543 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |