Extracts of seeds of 420 spp. of Leguminosae, in addition to those reported by Renkonen, Boyd and Reguera, and Boyd, were tested. A specific action was noted in 9 spp. The phto-agglutinins found are either anti-0 (Morgan and Watkins'' anti-H) type in some spp. of Genistease and Loteae, or anti-A type in some spp. of Galegeae, Viciae and Phaseolae. Anti-A phyto-agglutinin is specially interesting because its affinity for A1 cells is stronger than for A2cells; but it does not divide into 2 different antibodies as anti-A iso-agglutinin does.