Left palp. Good view of the seminal duct (the brown, winding snake-like tube) through which the semen travels - coming from the bottom, then up and around the curve and back to the left, then another curve (barely visible) and back up and to the right and on to the slender, needlelike embolus. The large, transparent greyish sclerite over top of it (and covering/protecting most of the middle to lower structures of the palp) is the tegulum.