✓ Pituitary glands from 500 consecutive autopsies were reviewed and the findings correlated with clinical symptomatology. Occult pituitary adenomas were identified in 42 pituitary glands (8.5%). In only one case was a pituitary lesion clinically questioned, but specific hypophyseal function studies were not performed. These tumors occurred most frequently in the sixth and seventh decade of life, without obvious sex predominance. Of these patients, 48% were obese, 57% were hypertensive, and diabetes mellitus was noted in 34%. Of the 17 cases in which skull x-ray films had been taken, suspicious or abnormal areas were found in 11. The tumor size ranged from 1 to 15 mm, but was greater than 1 cm in only one case. In 34 cases, the tumor was located along the periphery of the gland. Even though the etiological and functional significance of these tumors is unclear, the clinical course appears to be relatively benign.