Good serial sections of dried, mature cereal seeds can be made by first soaking the seeds for 24-48 hours in 5% aqueous hydrofluoric acid, fixing them in FA A (formaldehyde, ethyl alcohol and acetic acid solution), dehydrating in normal butyl alcohol, embedding them in paraffin, and soaking them in water for 12 hours just prior to sectioning. With this technic, one can obtain serial sections of an entire seed in one paraffin ribbon, 20μ thick.