Headache is a symptom met with in many forms of disease. It occurs in various kinds of intercranial mischief; it is a distressing symptom in most species of fever; it occurs in Bright's disease, in aneemia, in various uterine conditions in women, and in association with disturbances of the digestive system (the common bilious headache). A variety of headache recurring at intervals and sometimes involving only one side of the head is known as hemicrania or megrim. [Megrim.] Lastly, headache sometimes occurs apart from other symptoms, as the result, of worry and overwork of the brain. The term headache is not applied to every form of pain in the head; it must be distinguished from neuralgia of the nerves of the scalp, from the pain of ear disease, of glaucoma, and from the pains of inflammation of the bones of the skull. In children who complain of headache it will not infrequently be found that the eyes are at fault, and many a headache occurring in young persons has been cured by prescribing a suitable pair of glasses.