Fantastic monsters, such as acephalon, paracephalon, cyclops, pseudencephalon, and the janiceps, prosopthoracopagus, disprosopus, etc., although full of interest, will not be discussed here, as none are ever viable for any length of time, and the declared intention of this chapter is to include only those beings who have lived. CLASS VIII.--The next class includes the parasitic terata, monsters that consist of one perfect body, complete in every respect, but from the neighborhood of whose umbilicus depends some important portion of a second body. Pare, Benivenius, and Columbus describe adults with acephalous monsters attached to them. Schenck mentions 13 cases, 3 of which were observed by him. Aldrovandus shows 3 illustrations under the name of "monstrum bicorpum monocephalon." Bustorf speaks of a case in which the nates and lower extremities of one body proceeded out of the abdomen of the other, which was otherwise perfect. Reichel and Anderson mention a living parasitic monster, the inferior trunk of one body proceeding from the pectoral region of the other. Pare says that there was a man in Paris in 1530, quite forty years of age, who carried about a parasite without a head, which hung pendant from his belly. This individual was exhibited and drew great crowds. Pare appends an illustration, which is, perhaps, one of the most familiar in all teratology. He also gives a portrait of a man who had a parasitic head proceeding from his epigastrium, and who was born in Germany the same year that peace was made with the Swiss by King Francis. This creature lived to manhood and both heads were utilized in alimentation. Bartholinus details a history of an individual named Lazarus-Joannes Baptista Colloredo, born in Genoa in 1617, who exhibited himself all over Europe. From his epigastrium hung an imperfectly developed twin that had one thigh, hands, body, arms, and a well-formed head covered with hair, which in the normal position hung lowest. There were signs of independent existence in the parasite, movements of respiration, etc., but its eyes were closed, and, although saliva constantly dribbled from its open mouth, nothing was ever ingested. The genitals were imperfect and the arms ended in badly formed hands. Bartholinus examined this monster at twenty-two, and has given the best report, although while in Scotland in 1642 he was again examined, and accredited with being married and the father of several children who were fully and admirably developed. Moreau quotes a case of an infant similar in conformation to the foregoing monster, who was born in Switzerland in 1764, and whose supernumerary parts were amputated by means of a ligature. Winslow reported before the Academie Royale des Sciences the history of a girl of twelve who died at the Hotel-Dieu in 1733. She was of ordinary height and of fair conformation, with the exception that hanging from the left flank was the inferior half of another girl of diminutive proportions. The