Case 1st.—H. J. M. Admitted July 29th, 1872; female; 18 years; single. Hereditary predisposition existed in family; she had at one time been excited for a day or two, and been treated at home; she had lately been subject to considerable anxiety, and had to sit up frequently at night nursing a sick relative. Ten days ago became excited, talking much incoherently; was sleepless, and took food ill. For the two days previous to admission had got worse, more excited, had attacks of hysterics, and did not sleep at night. She had not menstruated for two months.