Pollen from twenty different grass species were prepared by a dehydration method and then examined with a light microscope (×800). Although differences were found between the grass pollen species, these were marked insufficiently to provide a key to identification of all the 20 species. Two grass species were found to show typical dehydration features permitting their identification. Pollen from 21 grass species were studied, using incident UV light microscopy. The colour of the cytoplasm, the colour shift of the cytoplasm, the colour of the pollen wall layers and the intensity of the autofluorescence were measured. By this autofluorescence technique 15 of the 21 grass pollen species could be identified.