Abstract
A system of microtubules has been demonstrated as a consistent feature within the Golgi apparatus of Euglena gracilis. The microtubules are between 12 and 17 nm in diameter and are usually positioned in the intercisternal space between adjacent cisternae. There are seldom more than 2–5 microtubules per dictyosome section, and these may be distributed variously throughout the stack. At least some of the microtubules are continuous with the surrounding cytoplasm, so they may act to transfer products into or out of the Golgi apparatus or as structural elements to orient or position the dictyosomes and secretion vesicles.