Two types of unusual transport mechanisms of antigens are described, one involving caterpillar hairs (setae) of gypsy moths, and the other involving grass pollen attracted to plastic sleds of an Alpine slide. Antigenic sources, investigations into peculiar mechanisms of spread, and impact of these antigens on allergic people are discussed. Each type affected allergic people in a different fashion, yet each type was associated with its own characteristically similar symptom complex. Natural factors terminated the gypsy moth antigen spread, but active interference into the Alpine slide antigen cycle was required for control.