Impact of weather changes on the growth of the unicellular Blepharisma undulans (Stein)

The growth of Blepharisma undulans (Stein) cells durably treated and not treated with insulin was followed up for three months with special regard a possible impact of meteorological factors on the growth rate. The growth rate of the protozoon was not appreciably altered by weather changes but the growth curves for cells treated and not treated with insulin indicated opposing trends of multiplication under the influence of approaching weather fronts. Warm fronts which have a parasympathic effect and cold fronts which have a sympathetic effect uniformly enhanced the growth rate of the untreated cells and retarded that of the insulin treated cells.