PLINY, THE YOUNGER 276 PLOVER Herculaneum and Pompeii were de- stroyed, in the first year of the Emi)€ror Titus. He wrote several works, which have perished, but his name and fame are preserved by his great work entitled "Natural History," in 37 books. It is a laborious compilation, on almost all branches of natural science, fine arts, inventions, and other subjects. It has been translated into most European lan- guages, and even into Arabic, and has been republished a very great number of times. PLINY, THE YOUNGER (Caius Plinius Caecilius Secundis), nephew of the preceding; born in Como A. D. 62. He studied under Quintilian, and in his 18th year began to plead in the forum. Soon after this he went as military trib- une to Syria. He settled at Rome; was promoted to the consular dignity by Trajan, in praise of whom he pronounced a famous oration, which is extant. He PLINY THE YOUNGER was afterward made proconsvd of Bi- th3mia, from whence he wrote to Trajan his curious and well-known account of- the Christians, and their manner of worship. The "Epistles of Pliny" are agreeably written, and very instructive; they were translated into English by Lord Orrey and Mr. Melmoth. He died after 112. PLIOCENE or PLEIOCENE, the epi- thet applied by Sir Charles Lyell to the most modern of the three periods into which he divided the Tertiary, Its dis- tinguished character is that the larger part of the fossil shells are of recent species. Lyell divides it into the Older and the Newer Pliocene. In the Older, the extinct species of shells form a large majority of the whole; in the Newer, the shells are almost all of living species. There is a rich Pliocene flora in Italy, Mr. Gaudin and the Marquis Strozzi enu- merate pine, oak, evergreen oak, plum, plane, elder, fig, laurel, maple, walnut, birch, buckthorn, etc. In the British Pliocene or Crag, Etheridge enumerates 328 genera, and 1,103 species of animals; 30 genera, and 57 species are mammalia. Both Vesuvius and Etna were in opera- tion. The climate, at first temperate, was becoming severe, and the Newer Pliocene was contemporaneous with part of the Glacial Period (q. v.). PLOCK, a town of Russian Poland, on the right bank of the Vistula, 60 miles N. W. of Warsaw. Its principal build- ing is the cathedral, built in the 11th cen- tury. One of the oldest towns in Po- land, Plock was the capital of ancient Masovia, and was severely ravaged by the heathen Prussians, the Lithuanians, and the Swedes. During the World War the town suffered severely by being bombarded and fought over in the strug- gle between German and Russian forces. Pop. about 40,000. PLOMBIERES, a town in the French department of Vosges, 14 miles S. of Epinal; sprang into fashion through the favor of Napoleon III., though the vir- tues of its waters were known ever since the times of the Romans. ^ There are nearly 30 springs, ranging in tempera- ture from 66° to 150° F.; their waters are helpful against skin diseases, gout, rheumatism, dyspepsia, female com- plaints, etc. The permanent population is about 2,000. PLOTINUS, a Greek philosopher, founder of the Neo-Platonic school; was born in Lycopolis, Egypt, A. D. 203. He was trained in the school of Alexandria, under Ammonius Saccas, then visited the East, and about 244 settled at Rome, where he spent the rest of his life as a teacher and writer. Porphyry, his most eminent disciple, wrote his life, and ar- ranged and published his works, divided into six sets of nine books each ("En- neads"). Plotinus was a profound thinker and a deeply religious man, and his system, a sort of mystical idealism, a combination of Platonic with Oriental notions. He died in Campania, in 270. PLOVER, the common English name of several wading birds; specifically, the golden yellow, or green plover, Chara- arius pluvialis. In winter the old male has all the upper parts sooty-black, with large golden-yellow spots on the margin of the backs of the feathers, the sides of the head, neck, and breast with ashy- brown and yellowish spots, the throat