Columbia Encyclopedia

(Encyclopedia) phlox, common name for plants of the genus Phlox and for members of the Polemoniaceae, a family of herbs (and some shrubs and vines) found chiefly in the W United States. The family includes many popu...

(Encyclopedia) snow-on-the-mountain: see spurge.

(Encyclopedia) Ohio, river, 981 mi (1,579 km) long, formed by the confluence of the Allegheny and Monongahela rivers in SW Pa., at Pittsburgh; it flows northwest, then generally southwest to enter the Mississippi Ri...

(Encyclopedia) Rio Grande rēˈō grănd, rēˈō gränˈdē [key], river, c.1,885 mi (3,000 km) long, rising in SW Colo. in the San Juan Mts. and flowing south through the middle of N.Mex., past Albuquerque, then c...

(Encyclopedia) United States Naval Observatory, a federal astronomical observatory, located in Washington, D. C. It evolved from the Navy's oldest scientific institution, the Depot of Charts and Instruments, founded...

(Encyclopedia) Akkad ăˈkăd, äˈkäd [key], ancient region of Mesopotamia, occupying the northern part of later Babylonia. The southern part was Sumer. In both regions city-states had begun to appear in the 4th m...

(Encyclopedia) Pacific Rim, term used to describe the nations bordering the Pacific Ocean and the island countries situated in it. In the post–World War II era, the Pacific Rim has become an increasingly important...

(Encyclopedia) pickerelweed, common name for the Pontederiaceae, a family of chiefly tropical perennial aquatic herbs found in freshwater. The pickerelweeds (genus Pontederia) range north into temperate regions, inc...

(Encyclopedia)  CE5 North America, third largest continent (2015 est. pop. 571,949,000), c.9,400,000 sq mi (24,346,000 sq km), the northern of the two continents of the Western Hemisphere. North America includes a...

(Encyclopedia) Pan-American Highway, system of roads, c.16,000 mi (25,750 km) long, linking the nations of the Western Hemisphere. It was suggested at the Fifth International Conference of American States (1923) and...