Observations morphologiques sur Polyaspis patavinus Berlese 1881 (acariens: uropodides). 2. Morphologic et chetotaxie des appendices au cours du developpement postembryonnaire. -The legs morphology and chaetotaxy of P. patavinus are studied during the ontogenetic development. Special attention is given to the setae of tarsi I; owing to a provisional nomenclature is proposed. The palpal chaet taxy, es ecially the tibiotarsal one, is observed. P. patavinits occurs in the temperate and mediterranean regions in Europe. This species inhabits the saproxylic biotopes; the phoretic stasis are captured on xylophageous Coleoptera (Lucanidae) chiefly in the summer. The main specific criterions are presented as discussion. On a morphological point of view, the Polyaspidae are readily distinguished from the other Trachytoïdea; in the genus Polyaspis s.l. the situation of the genital setae st5 is an interesting primitive feature.