1. The number 4 trisome is now available in a stock segregating for su l. Also, all of the other trisomes, with the exception of number 1, are available in vigorous stock cytologically determined to be free of B chromosomes. To make these trisomic stocks wore suitable for use in the corn belt and elsewhere, they have been outcrossed to different commercial inbred lines, including the corn belt lines Hy and 187--2 and somewhat earlier maturing New York State lines of Luce's Favorite and Cornell 11.