In a previous report it was shown1that the nonpathogenic spores of molds found in the air are frequent causes of asthma and nasal allergy. Thus far no emphasis has been placed on the fact that these symptoms frequently assume a seasonal character and become confused with pollen hay fever and asthma. It is my purpose in this paper to call attention to a group of patients whose respiratory manifestations are confined to the summer or aggravated in that season by sensitiveness to fungi instead of pollen. Over a period of several years, impressions gained from clinical and laboratory observations with respect to seasonal hay fever and asthma culminated three or four years ago in the belief that these symptoms are not always due to pollen. The fact that there are many patients who respond only partially or not at all to pollen treatment led to the suspicion that