Carbon dioxide compensation points of several hundred species of monocotyledons and dicotyledons have been measured during the course of various experiments in our laboratory over a period of several years. These have been classified into two groups: high, compensation points of 40 mul/l or greater; and low, compensation points of 10 mul/l or less. They are listed alphabetically both by families and species for monocotyledons and dicotyledons. Only two species did not unequivocally fit into the above established groups. These were Moricandia arvensis (L.) DC., which had an average compensation point of 26 mul/l and Panicum milioides Nees ex Trin., which was variable, but most often equilibrated between 12 to 20 mul/l CO(2).