Langdon Down suggested that the physiognomical features of certain defectives enabled them to be arranged in ethnic groups; of these he differentiated Mongolian, Ethiopian, Caucasian, and American Indian. Such an ethnic classification has been abandoned, but the term “mongolism” has been used to describe one important variety of ailment, although recently giving way to “Down’s syndrome”, for an explanation of which, see N. Howard-Jones, Med. Hist., 1979, 23, 102-04.