Translations of scientific and technical monographs and articles.

The Arctic region has long held a fascination for explorers and scientists of many countries. Despite the numerous voyages of exploration, the na ture of the central Arctic was unknown only 90 years ago; it was believed to be a shallow sea dotted with islands. During Nansen's historic voyage on the polarship Fram, which commenced in 1893, the great depth of the central basin was discovered. In the Soviet Union, investigation of the Arctic Ocean became national policy after 1917. Today research at several scientific institutions there is devoted primarily to the study of the North Polar Ocean and seas. The systematic exploration of the Arctic by the United States com menced in 1951. Research has been conducted year-round from drifting ice islands, which are tabular fragments of glacier ice that break away from ice shelves. Most frequently, ice islands originate off the northern coast of Ellesmere Island. These research platforms are occupied as weather sta tions, as well as for oceanographic and geophysical studies. Several inter national projects, conducted by Canadian, European, and U. S. groups, have been underway during the last three decades. Although much new data have accumulated since the publication of the Marine Geology and Oceanography of the Arctic Seas volume in 1974 (Yvonne Herman, ed. ), in various fields of polar research-including present-day ice cover, hydrogra phy, fauna, flora, and geology-many questions remain to be answered.

From single-celled organisms in Black Sea sand to endemic cave crustaceans, from mountain glacial relict insects to the most diverse bird fauna in Europe, the fauna of Bulgaria has been a subject of study for more than a century. This is the first English language survey of all vertebrate and many key invertebrate groups of Bulgaria, their faunistics, origin, geographical and ecological distribution, and conservation issues.

Translation of: Atlas bespozvonochnykh dal'nevostochnykh morey SSSR. Moscow-Leningrad, Izdatel'stvo Akademii Nauk SSSR, 1955.

Gastropods on land: phylogeny, diversity and adaptive morphology; Body wall: form and function; Sensory organs and the nervous system; Radular structure and function; Structure and function of the digestive system in Stylommatophora; Food and feeding behaviour; Haemolymph: blood cell morphology and function; Structure and functioning of the reproductive system; Regulation of growth and reproduction; Spermatogenesis and oogenesis; Population and conservation genetics; Life history strategies; Behavioural ecology: on doing the right thing, in the right place at the right time; Soil biology and ecotoxicology.