The fine structure and functioning of tissue channels and lymphatics.

The fine structures of the tissue channels and the lymphatics are described. The two systems form part of the whole blood vascular-tissue channel-lymphatic complex. The fine functioning of this is very dependent on the structures of its individual components. In brief, the tissue-lymphatic system is a leaky swamp through which material flows due to the vagaries of adjacent pressure changes. It enters the lymphatics via holes in their walls: it is retained in them when the holes are closed.