Nomenclature, filling and angioarchitecture of lymph vessels in organs. Scanning electron microscopy of the stomach of the turtle Pseudemys scripta elegans using different injection methods.

The gastric lymph vessel network of Pseudemys scripta elegans shows all the characteristics of initial lymphatics. A differentiation of initial lymphatics in lymphatic capillaries and precollectors is not possible in the turtle. The scanning electron microscopic examination shows that ultrastructural analysis of initial lymphatics is possible after manual subserous injection of glutaraldehyde or application with the vacuum chamber. In the stomach of the turtle all characteristics of initial lymphatics (interendothelial openings, subendothelial filaments, connective tissue trabeculae and endothelial bridges) could be demonstrated. Only valves were absent. The situation is similar in mammals including man. The most important filling phenomenon is a horizontal spreading of fluid in the lymphatics.