=Pla´to.= A celebrated philosopher of Athens. He was educated carefully, his mind being cultivated by the study of poetry and geometry, whilst his body was invigorated by the practice of gymnastics. He began his literary career by writing poetry and tragedies. At the age of twenty he was introduced to Socrates, with whom he was for some time a pupil. After traveling in various countries, he retired to the neighborhood of Athens, where his lectures were attended by a crowd of learned, noble, and illustrious pupils. He died on his birthday in the eighty-first year of his age, about 348 years before the Christian era. His writings were so celebrated, and his opinions so highly regarded, that he was called the Divine. =Plau´tus, M. Ac´cius.= A dramatic poet born in Umbria. He wrote twenty-five comedies, of which only nineteen are extant. He died about 184 years before the Christian era. =Plei´ades.= A name given to seven daughters of Atlas and Pleione. They were placed after death in the heavens, and formed a constellation. =Plin´ius, C. Secun´dus=, called the Elder, was born at Verona, of a noble family. He distinguished himself in the field, and was appointed governor of Spain. When at Misenum in command of the Roman fleet, Pliny observed the appearance of a cloud of dust and ashes, which was the commencement of the famous eruption of Mount Vesuvius which overwhelmed Herculaneum and Pompeii. He sailed for the scene of the eruption, where he was suffocated by the vapors emitted. This occurred in the seventy-ninth year of the Christian era. =Plin´ius, C. Cæcil´ius Secun´dus=, surnamed the Younger Pliny, was son of L. Cæcilius by the sister of Pliny the Elder. At the age of nineteen he distinguished himself at the bar. When Trajan was invested with the purple Pliny was created consul. He died in the fifty-second year of his age, A.D. 113. Pliny had much to do with the persecutions of the Christians in the early promulgation of the Christian religion. The Rev. James Copland, M. A., in an admirable little work entitled "Reasons why we Believe the Bible," gives a very interesting letter from Pliny to the emperor Trajan, asking instructions how to deal with the Christians when they were cited to appear before him. =Plutar´chus=, the celebrated biographer, was born at Chæronea, his father being distinguished for his learning and virtues. After traveling in quest of knowledge, he retired to Rome, where he opened a school. Subsequently he removed to Chæronea, where he died at an advanced age about the 140th year of the Christian era. His most esteemed work is the Lives of Illustrious Men. =Plu´to=, son of Saturn and Ops, inherited his father's kingdom with his brothers, Jupiter and Neptune. He received as his portion the kingdom of the infernal regions, of death, and funerals. He seized Proserpine as she was gathering flowers, and carrying her away on his chariot, she became his wife and queen of the infernal regions.