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Are the extreme radicles of the arteries and veins, which together constitute the capillary, intermediate, or peripheral vascular system-the methoe'mata or methaematous blood-channels of Dr. Marshall Hall. They possess an action distinct from that of the heart, but not one of rhythmic contraction and dilatation. Formerly, it was conceived that white vessels-Vasa sero'sa-or vessels so minute as not to admit red corpuscles, were distributed to the tissues which do not receive red blood.

(Anat.) A network of minute vessels, connecting the veins and the arteries.

C. leaves (Bot.), hair-like; e.g. fennel.