In a series of 9 cases of hypertensive pheochromocytoma, the author noted in five of them abolition of the lower abdominal skin reflex on the same side as the tumour. They were in four cases suprarenal pheochromocytomas and in the fifth case an ectopic paraganglioma of Zuckerland's organ. In 3 cases, the abolished reflex became normal and equal to that on the opposite side after removal of the tumour. In two others, it remained abolished. In 4 patients, most of the other abdominal skin reflexes, expecially those, on the opposite side, very brisk before the operation, became normal afterwards. The author concludes that in cases of hypertensive pheochromocytoma, careful study of the abdominal skin reflexes may provide a useful contribution to topographic diagnosis.