We shall, however, say a few words about another infirmity--incontinence of urine. If there is presented for a class for defectives a subject, eleven years of age, who cannot control himself in this respect, the course to follow is: submit the child to examination by a specialist, who will decide the nature of the incontinence. If it is curable, give the condition the necessary attention, or give instructions at the school for training the child properly; but if there is an incurable weakness of the sphincters, supply the child with the same kind of apparatus as is used in such cases by ordinary people. * * * * * Here, then, are a number of important points upon which the doctor may be called to give his opinion. It is he alone who is able, by his special knowledge, to enlighten the other members of the jury. If the mental condition is doubtful and requires further observation, it is for him to point it out. One will thus avoid the mistake of placing in a class for defectives a lunatic, or a child poisoned by alcohol, who would not find there the kind of care required. If the bodily condition discovered complicates or aggravates the mental deficiency, as adenoid vegetations may do, he will prescribe the proper treatment. If he suspects the coexistence of some neurosis, he will give directions by which the condition may be recognised, and consequently treated. The doctor therefore has to recognise the physical and mental ailments by which the defective may be affected. He makes this diagnosis for two reasons. In the first place, in order that mental deficiency may not be confounded with conditions of illness of a different kind; and, secondly, in order to relieve or cure if possible coexisting affections which may aggravate the condition of the children and interfere with the work of the school. * * * * * We shall conclude here what we have to say about the rôle of the doctor, since in this volume we are specially concerned with the recognition and segregation of the children. To discuss the rôle of the doctor quite fully would take us too far. The details we have given show that the part of the doctor with regard to defectives is quite different from that of the teacher. It is not so much to determine the child's precise mental level as to diagnose the condition of his brain, and to discover, by analysis of all the symptoms, the original responsible agent. That, however, is the second part of the doctor's work, and is of scientific interest; whereas the first part, which consists in diagnosing the ailments which co-exist with the mental deficiency, is of immediate practical utility.