As recently reported we isolated from a lipolytically active pituitary crude fraction P IV three other peptides which showed lipolytic activity but also same corticotropic activity. From these three fractions we obtained twelve other subfractions by ion exchange chromatography. Three of these fractions showed high lipid mobilizing effects. For two of these lipolytic fractions no corticotropie activity was demonstrable by the radioimmunological assay; in vitra these two fractions did not stimulate the corticosterone secretion. Herewith, it was for the first time possible to isolate peptides from hog pituitaries wh ich showed high lipolytic activity but no corticotropie activity.