This lymphatic fluid is then transported via progressively larger lymphatic vessels through lymph nodes, where substances are removed by tissue lymphocytes and circulating lymphocytes are added to the fluid, before emptying ultimately into the right or the left subclavian vein, where it mixes with central venous blood.

The lymph formed in the human digestive system called chyle is rich in triglycerides (fat), and looks milky white because of its lipid content.

[4] (Prior to entry, this fluid is referred to as the lymph obligatory load, or LOL, as the lymphatic system is effectively "obliged" to return it to the cardiovascular network.

Tubular vessels transport lymph back to the blood, ultimately replacing the volume lost during the formation of the interstitial fluid.

[8] Despite low pressure, lymph movement occurs due to peristalsis (propulsion of the lymph due to alternate contraction and relaxation of smooth muscle tissue), valves, and compression during contraction of adjacent skeletal muscle and arterial pulsation.

If excessive hydrostatic pressure develops within the lymph vessels, though, some fluid can leak back into the interstitial spaces and contribute to formation of edema.

[13] In 1907 the zoologist Ross Granville Harrison demonstrated the growth of frog nerve cell processes in a medium of clotted lymph.

In 1913, E. Steinhardt, C. Israeli, and R. A. Lambert grew vaccinia virus in fragments of tissue culture from guinea pig cornea grown in lymph.