In: Pedobiologia, 1988, 31 (1-2), pp.1-64. This paper is the third in a series, the aim of which is to demonstrate the value of micromorphological investigations in soil ecological studies. After microstratification of a soil sample from a Scots pine stand (Forêt d'Orléans, Loiret, France), the F1 layer was studied using the following procedures: 1. Sorting the different components under adissecting microscope, 2. Counting and measuring soil animaIs, observing their digestive tract by clearing or after dissection, and by mounting their faeces, 3. Thin-sectioning different types of vegetation,observing these sections under a light microscope with an appropriate stain procedure. The principal results from this study concern the de composition of pine needles, twigs and bark, ecto-mycorrhizae and their associate mycelia (Cenococcum geophilum and several basidiomycetes), decomposition of mosses (Pseudoscleropodium pururn), bracken leaves and animal bodies in the F1 layer.