An eminent Russian naturalist, born in Mitau, Russia; studied science at Berlin and Vienna; held the chairs of Zoology and Midwifery at Kasan and Wilna, and of Palæontology at St. Petersburg; his explorations, which led him through most of Europe, Persia, and Algeria, and included a survey of the Baltic shores, as well as expeditions into the Caucasus, are described in his various works, and their valuable results noted (1795-1876).