%0 Journal Article %A Selman, G. G. %A Jurand, A. %T Trichocyst Development During the Fission Cycle of Paramecium %D 1970 %J Microbiology, %V 60 %N 3 %P 365-372 %@ 1465-2080 %R https://doi.org/10.1099/00221287-60-3-365 %I Microbiology Society, %X SUMMARY: In Paramecium aurelia, pretrichocysts originate in the endoplasm as undifferentiated vesicles. They develop in the endoplasm and then migrate to sites below the pellicle to become juvenile trichocysts. The maturation process takes place below the pellicle and involves a physical expansion and change in staining affinity of the body material of the trichocyst. Cold fixation usually caused mature trichocysts to be extruded, but the use of osmium tetroxide fixative at 37° allowed them to be fixed without extrusion. Juvenile trichocysts cannot be extruded. In P. bursaria and P. aurelia after osmic fixation the body of the mature trichocyst, unlike the juvenile trichocyst, had no staining affinity for either potassium permanganate or toluidine blue. During fission in P. aurelia, mature trichocysts were present only in small numbers at the poles of the protozoa remote from the furrow. Juvenile trichocysts mature in the first hour of the interfission period. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-60-3-365