In the absence of evident signs of external injury, cases of focal epilepsy in the young require careful investigation, inquiry being made as to difficult labour, for, as Harvey Cushing points out, ‘When we consider the widespread lesions associated with those cases that later on are recognizable as Little’s disease, and that presumably an enormous number of children receive at birth some trifling injury which, from lack of symptoms, is overlooked, may it not be that many cases of so-called idiopathic epilepsy dating from childhood can be safely attributed to the effects of early traumatism?’ In all these, and in other doubtful cases, before undertaking surgical procedures, the surgeon should obtain the services of a skilled neurologist. =The clinical course of the case.= If a typical case of Jacksonian epilepsy can be observed from beginning to end, many curious and interesting features will be observed. The fits, at first typically Jacksonian, gradually lose their typical character, becoming more frequent and less focal in nature, the patient losing consciousness during the fit, and the fits succeeded by weakness or paralysis of the parts primarily involved. The general mental state of the patient suffers proportionately--he becomes morose, despondent, irritable, homicidal, or suicidal in tendency. How far these retrograde symptoms are dependent on degenerative processes in the brain, and how much they result from the moral effect of the frequent epileptiform seizures, are questions that can only be determined by observing the effect of treatment, surgical or otherwise. Some cases respond readily to treatment, others are too far advanced to experience any material benefit, some end their days in the lunatic asylum. In any case, surgical treatment, if adopted at all, must be carried out before definite brain-degeneration arises--such changes being evidenced by spasticity of the limbs, exaggerated knee-jerks, &c. When such pathological changes are existent, there can be but little hope of benefiting the patient. Further points in the clinical course of the case, and such also as throw further light on the pathological conditions present, will be obtained by a survey of 21 cases that have come under my own care or close observation. _Time elapsing between the date of the accident and the first fit._ Between 1 and 19 years 9 cases Within 8 months 9 cases After a few days 1 case Uncertain 2 cases _Age at time of accident._ Before 15, 12 cases. Youngest, 3 years. After 15, 9 cases. Oldest, 55 years. _Sex._ Males 20. Females 1. _Conditions found on external examination and on operation._ External examination: Depression of bone and scar, 6 cases. Deficiency of bone, 3 cases. Scar only, 5 cases. Nil, 7 cases.