A suite of core samples for palynological examination was macerated, observing the usual precautions against contamination. The resulting microflora assemblage was erratic. Contamination was introduced through the technical grade reagents used. Examination of the slight sediment present in technical grade hydrochloric and nitric acid reagent bottles revealed abundant plant tissue, diatoms, and some spores and pollen. It is suggested that chemically pure grade reagents will eliminate contamination.