To determine the optimum population density range of PSC 355 and two experimental PhytoGen varieties PH98M-2983 and PH98M-3196, a study was conducted on a fine sandy loam soil in Leland, MS. Each variety was planted on 40” rows at targeted seeding rates ranging from 10,000 to 70,0000 plants/acre. For each variety, the effect of varying plant populations on lint yield, plant height and maturity were evaluated. Based on the analyses of plant populations closest to 15,000, 25,000, 45,000 and 65,000 plants per acre for each variety, the highest yields were achieved at the 45,000 plant per acre range. The data suggests that the consistent performance of PSC 355 may be partially explained by the ability of the variety to perform well at plant populations ranging from 13,000 to almost 65,000 plants per acre. Yield potential of the two new experimental varieties appear to be equal to or greater than PSC 355. No significant differences were detected in the maturity or height of these varieties at the four plant populations analyzed. Excessive boll rot associated with heavy rains and high humidity in late August and early September may have masked some differences in the results. Additional studies are needed to further define the effect of plant populations on the yield and development of these varieties under different growing locations and seasons.