While alluding to other technics this review was confined to the microdis-. section method[long dash]by frozen sections, by section of tissues in suitable imbedding media, by dividing cells with glass needles, or by centrifuging cells. Accessory to this ap-proach were ingenious micromethods for estimating quantity of sample from measurements of volume, weight, N content, and other standards of reference. The enzymatic methods discussed were titrimetric, manometric, calorimetric, and dilatometric. Selected applications to histochemical, cyto-chemical, and embryological expts. were cited.