Swarm Cell Ultrastructure in Ceratiomyxa Fruticulosa

SUMMARY

Swarm cells of Ceratiomyxa fruticulosa consistently contain two basal bodies although both uniflagellate and biflagellate forms coexist. Basal body and flagellar ultrastructure are typical of eukaryotic motile cells. A mitochondrion and Golgi body are located between the cell nucleus and the basal bodies. The posterior region of the cell typically contains a food vacuole and mitochondria. Thin sections of swarm cells stained with a combination of phosphotungstic acid and KMnO₄ demonstrate a distinct surface coat composed of fine fibrils approximately 75 Å thick which extend about 120 mμ from the cell surface. The fibrils branch at their tips forming a latticelike network over the surface of the swarm cells.