4. Studies on induced polyploidy and other genetic effects induced by heat treatments were continued during the past year. My stocks of tetraploid corn looked much better last year than ever before in spite of the generally unfavorable weather conditions; good vigor, and a very sturdy growth habit characterized a number of lines which were also highly fertile and in other respects looked very promising. Tetraploidy was induced in both the Durango and Florida types of annual teosinte. These experimentally induced tetraploids were entirely annual with no trace of the perennial habit which characterizes the tetraploid Euchlaena perennis from Mexico. One octoploid was also obtained and it wasn't perennial either, but was dwarfed and sterile like the corn octoploids.