membranous layer membranous layer the membranous layer or stratum membranosum is the deepest layer of subcutaneous tissue. it is a fusion of fibres into a homogeneous layer below the adipose tissue, for example, superficial to muscular fascias. membranous layerdetailsidentifierslatinstratum membranosumta98a16.0.03.005ta27093, 7095fma82496anatomical terminology it is considered a fascia by some sources, but not by others. however, prominent areas of the membranous layer are called fascias; these include the fascia of scarpa in the abdomen and the fascia of colles in the perineum.