[The attachment response of the cercaria of Schistosoma mansoni. Influence of natural substrates and temperature (author's transl)].

The behaviour of the cercaria, following contact with different animal and human substrates during swimming, has been studied. Four patterns of behavior related to the intensity of stimulation can be distinguished: 1. backward reaction, 2. stopping, 3. forward reaction, 4. attachment (Figs. 2 and 3). Mechanical stimulation of the cercaria by touching or water turbulence, prior to contact with the substrate has an insignificant effect on attachment. Both attachment and the first step in penetration (crawling over the substrate) are stimulated by a rise in temperature (Figs. 4 and 5) and the chemical properties of the substrate. However, the steps in penetration may possibly be stimulated by chemical components and perceived by receptors different from those involved in attachment.