|1.||David. 1813--73, Scottish missionary and explorer in Africa. After working as a missionary in Botswana, he led a series of expeditions and was the first European to discover Lake Ngami (1849), the Zambezi River (1851), the Victoria Falls (1855), and Lake Malawi (1859). In 1866 he set out to search for the source of the Nile and was found in dire straits and rescued (1871) by the journalist H. M. Stanley|
|2.||Kenneth Robert, known as Ken. born 1945, mayor of London from 2000; Labour leader of the Greater London Council (1981--86)|
(genus Lithops) any of a group of about 40 species of succulent plants of the carpetweed family (Aizoaceae), native to southern Africa. The plants are virtually stemless, the thickened leaves being more or less buried in the soil with only the tips visible. Two leaves grow during each rainy season and form a fleshy, roundish structure that is slit across the top. Flowers grow between the slit, and then a shoot (with two leaves) grows from the axils of one or both of the leaves, which then shrivel. Living stones spread sideways, and one plant may have the appearance of several stones. They are cultivated worldwide as indoor plant curiosities.
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