=Styes.=—Styes are a very painful species of small boils that generally form on the edges of the eyelids. They are apt to appear in succession. Certain persons are liable to them if the system is run down from general causes. Like boils in other parts of the body, they give evidence of impaired nutrition. Hot fomentations of boric acid solution will sometimes abort them if used early. If pus has formed, the stye must be opened by an incision parallel to the edge of the lid. This should not be attempted by any one except a physician. =Color-blindness.=—As a rule, about 4 per cent. of males and about one-half of 1 per cent. of females are color-blind. The part of the color sense that is most often deficient is that for green and red. =Cataract.=—This is a disease in which the crystalline lens or its capsule, or both, lose their transparency and become opaque. Eventually total blindness is the result. Senile cataracts appear after the forty-eighth year. The only remedy for the disease is the surgeon’s knife. =Functional Nervous Disorders.=—Evidences of sound health are: first, individual adaptability or capacity of the individual to easily adapt herself to extremely opposite conditions of existence; second, endurance, or the capacity to do a considerable amount of mental work for a short time without suffering fatigue, or to be able to quickly recover from the fatigue; third, to be able to control the emotions; fourth, to be able to resist morbific influence; that is, the capacity on the part of sound organs of excretion to quickly eliminate all poisons from the system. The signs of debility are just the reverse: first, deformity, obesity, or leanness; second, personal inadaptability, that is, when physical or mental discomfort is caused by such slight provocations as change of food, clothing, or climate; third, lack of endurance, so that a long rest is required to repair the fatigue incident to slight exertion; fourth, lack of control of the emotions; fifth, a proclivity to morbific influences, so that the individual succumbs to every contagion or miasm that she encounters. Nervousness is a disease of civilization, coupled with overwork and indoor life. The more complex the environment in which the individual finds herself, and to which she must adjust herself, the greater the demands made on the nervous system. The extreme dryness of our climate, together with the great variations of temperature between winter and summer and the rapid fluctuations of temperature, predisposes to nervous disorders. =Headache.=—Headache is a symptom rather than a disease, but there is no symptom which requires more careful investigation of its cause than that of headache. It occurs at all ages, but is most common from ten to twenty-five years and from thirty-five to forty-five years. Women suffer from headache more than men, in the proportion of about three to one. Headaches are most common in the spring and fall of the year and in the temperate climates.