| Author Title Journal |
Mattes O (1932) Uber die Wirkungsweise und die Bedeutung der Turbellarien-Hautdrusen. Zeit Schr Wiss Biol Abt A Zeitschr Morph U Okol Tiere 24(3/4): 743-767 |
Abstract / Notes
Miracidia of Fasciola hepatica, in search of an intermediate host, even attempt to bore into planaria. Although injured by the skin poisons of the planaria, they continue boring until incapable of movement. These trematode larvae, therefore, may be used as natural aids in ascertaining the action of turbellarian skin glands. Four spp. of planaria were examined: Planaria lugubris, P. gonocephala, Dendrocoelum lacteum, and Polycelis nigra. The injuring effect appeared to be of the same kind but of varying degree for the 4 spp. The strength of the effect is also dependent on the state of irritability of the planaria. Disturbed animals, on account of increased secretion, have an effect considerably more poisonous than ones not disturbed. Contact with stimulated animals can cause death of the miracidia. Ordinarily the characteristic paralysis appears first, and only gradually leads to death. The injuries take place not only directly on the bodies of the planaria, but also from the isolated mucus. On the contrary the tissue pulp, obtained by grinding the planaria, seems not to be poisonous. The poison mucus of planaria makes an effective protective medium against parasites that seek to penetrate through the skin, and also against predaceous Crustacea and insect larvae which, as further experiments showed, were driven away at the first contact.| Home page -- (Main hierarchy) |