Medical scientist. Born in Settle (Yorkshire), Riley studied medicine at the University of Edinburgh, graduating in 1935. He served with the Scottish Emergency Medical Service during Second World War. He completed his doctorate in Edinburgh in 1946 and went on the undertake research in radiology, with particular interest in the use of x-rays to treat cancer.
He was appointed as Consultant Radiologist at Dundee Royal Infirmary (1948) and took on the additional role of Reader in Radiotherapy at the University of St. Andrews (1950). His research included the study of mast cells, discovering the origin of histamine and contributed greatly to understanding allergic conditions such as asthma and anaphylactic shock.
He was elected a Fellow of the Royal College of Surgeons of Edinburgh in 1938 and a Fellow of the Royal Society of Edinburgh (1968).
He retired in 1976 and died in St Andrews. He is remembered within Discovery Walk in Slessor Gardens on Dundee's Waterfront.