Development of compound trichocysts in the ciliatePseudomicrothorax dubius

Summary During the logarithmic growth of the ciliatePseudomicrothorax dubius associations between mitochondria, rough endoplasmic reticulum and dictyosomes have been observed. The Golgi apparatus is very active and it is suggested that, as a consequence of cytotic activity, the contents of the Golgi vesicles become incorporated into large irregular vacuoles as globular material. The large vacuoles develop into trichocysts and the dictyosome derived globules consolidate to ultimately form the rod-like arms of the trichocysts of theMicrothoracidae.