The T and B lymphocytes were identified by means of the rosette tests in the peripheral blood of 79 patients with respiratory allergies of whom 41 with allergic rhinitis and 38 with bronchial pollen asthma, as well as in 16 control subjects. The results have shown a clear lessening of the T cells (both in per cent and absolute values) and a less significant decrease of the B cells (only in absolute values) in the patients as compared with the controls. These data suggest an immune deficiency which did not differ between the two groups of patients and was not influenced by the specific hyposensitizing treatment.