CLASS IX.--Of "Lusus naturae" none is more curious than that of duplication of the lower extremities. Pare says that on January 9, 1529, there was living in Germany a male infant having four legs and four arms. In Paris, at the Academie des Sciences, on September 6, 1830, there was presented by Madame Hen, a midwife, a living male child with four legs, the anus being nearly below the middle of the third buttock; and the scrotum between the two left thighs, the testicles not yet descended. There was a well-formed and single pelvis, and the supernumerary legs were immovable. Aldrovandus mentions several similar instances, and gives the figure of one born in Rome; he also describes several quadruped birds. Bardsley speaks of a male child with one head, four arms, four legs, and double generative organs. He gives a portrait of the child when it was a little over a year old. Heschl published in Vienna in 1878 a description of a girl of seventeen, who instead of having a duplication of the superior body, as in "Millie-Christine, the two-headed nightingale," had double parts below the second lumbar vertebra. Her head and upper body resembled a comely, delicate girl of twelve. Wells a describes Mrs. B., aged twenty, still alive and healthy. The duplication in this case begins just above the waist, the spinal column dividing at the third lumbar vertebra, below this point everything being double. Micturition and defecation occur at different times, but menstruation occurs simultaneously. She was married at nineteen, and became pregnant a year later on the left side, but abortion was induced at the fourth month on account of persistent nausea and the expectation of impossible delivery. Whaley, in speaking of this case, said Mrs. B. utilized her outside legs for walking; he also remarks that when he informed her that she was pregnant on the left side she replied, "I think you are mistaken; if it had been on my right side I would come nearer believing it;"--and after further questioning he found, from the patient's observation, that her right genitals were almost invariably used for coitus. Bechlinger of Para, Brazil, describes a woman of twenty-five, a native of Martinique, whose father was French and mother a quadroon, who had a modified duplication of the lower body. There was a third leg attached to a continuation of the processus coceygeus of the sacrum, and in addition to well developed mammae regularly situated, there were two rudimentary ones close together above the pubes. There were two vaginae and two well-developed vulvae, both having equally developed sensations. The sexual appetite was markedly developed, and coitus was practised in both vaginae. A somewhat similar case, possibly the same, is that of Blanche Dumas, born in 1860. She had a very broad pelvis, two imperfectly developed legs, and a supernumerary limb attached to the symphysis, without a joint, but with slight passive movement. There was a duplication of bowel, bladder, and