Cell division in Tetrahymena occurs by lateral binary fission and results in an anterior proter and a posterior opisthe. Prior to division rows of basal bodies elongate as new basal bodies are formed next to preexisting basal bodies. The cell essentially doubles in length but not in width. A new oral region and a new contractile vacuole form and in amicronucleate strains the macronucleus divides. TEM taken on 8/8/67 by R. Allen with Philips 200 operating at 60kV. Neg. 1,800X. The raw negative was scanned with an Epson Perfection V750 Pro and this high resolution image is best used for quantitative analysis. Additional information available at (http://www5.pbrc.hawaii.edu/allen/).