Abstract
Adm. of an extract of bull testes caused (1) decrease in pituitary wt. with an increase in size of the basophil cells of the ant. lobe, (2) no change in thyroid wt., but larger, more uniform acini, paler staining colloid, flat epithelium, increase in connective tissue stroma, and pyknotic changes in the nuclei, and (3) hypertrophy and hyperplasia of the adrenals.