[Ecological study of Ixodes ricinus (Linné, 1758) (Acarina, Ixodoides) in southeastern France].

Ixodes ricinus (LINNE, 1758) is being surveyed in the northern Alp and the Jura mountains. This species, quite often found in the mesophilous forests of the hills, preferably takes root in the forest clusters, where there is a mull type mild humus often covered with an abundant litter. Such plant layers maintain a high degree of moisture, which beneficially affects this species. Examinations performed for three years in a southern Jura's resort allow for securing a preliminary approximation as regards the seasonal population variations.