Visual Methods
This procedure is taken from those of Absher (1973), Freshney (2000), Merchant et al. (1964), and Phillips (1973). The most practical method for routine determina- tion of the number of cells that are in suspension or that can be put into suspension is a direct count in a hemocytometer. The hemocytometer is a modified glass slide engraved with two counting chambers of known area. Each chamber grid is composed of nine squares (subgrids), with each square being I mm 2 (see Fig. 1). The hemocytometer is supplied with a glass coverslip of precise thickness that is supported 0.100mm above the ruled area.