False colour scanning electron micrograph (SEM) of a pollen grain attached to the stigma of the cocksfoot grass, Dactylis glomerata. Cocksfoot pollen, a summer grass pollen dispersed by the wind, is a major cause of hay fever (medical name Allergic rhinitis & pollenosis). Hay fever suffer- ers produce a sensitising antibody, immunoglobin E (IgE), which attaches to the surface of cells in the nose & eyes. It reacts with inhaled pollen (an allergen) causing the release of various chemic- als including histamine. Histamine causes the muc- ous membranes of the nose, eyes & throat to swell & become inflamed, bringing on the symptoms of hay fever. Magnification: X385 at 35mm size. original is bw print B786/072