One of the ANBG gardeners cut off part of a Leptospermum branch and, in doing so, also cut through a Phellinus, leaving about half of it there. In the second photo the arrow points to a paler, narrow band at the bottom of the fruit body, composed of numerous tubes of very tiny diameter. At their lower ends the tubes are open. The walls of those tubes are lined with basidia (the spore-producing organs). When the spores are released from basidia they fall down, through the tubes, out through the tube mouths and are then carried further afield by wind. For the spores to be able to escape, the tubes must be aligned vertically. The darker part of this fruit body is a spore-less, sterile supporting structure for that narrow fertile area. In the third photo I show a close up, side-on view of those numerous tiny tubes. I am accustomed to doing cross-sections by scalpel or razor-blade and was quite impressed with this example of cross-section by chainsaw.