German naturalist at the Russian Academy of Sciences in St. Petersburg. Peter Simon Pallas is amongst the most prolific collectors and explorers of European Russia, Siberia and Central Asia and, unlike many of his contemporaries, published a great deal of his findings. This includes major works on the Russian flora and fauna.

Pallas was born and raised in Berlin and in his early years schooled by his father, a professor at the Medical-Surgical Academy. Later he attended this academy (1754-1759) as well as studying at the universities of Halle, Göttingen and Leiden, where he received his doctorate in 1860 for a thesis contesting the Linnaean classification of worms. Continuing to pursue an interest in the invertebrates, Pallas visited London (where he was elected to the Royal Society in 1763) and Holland in order to study marine animals between 1761 and 1766. From these studies he produced Elenchus zoophytorium (1766), in which he championed a classification system for the corals and sponges within the animal kingdom.

On his return Pallas was invited to St. Petersburg and in 1767 he became an ordinary academician at the Academy of Sciences. Here he was soon involved in the vast array of expeditions which Catherine II was supporting to mark the transit of Venus, and was nominated leader of the first of a series of expeditions to Orenburg. His detachment left in the summer of 1786 and first travelled to Moscow, before setting out for Ulyanovsk where they crossed the Volga. Continuing on to Tobolsk they explored the banks of the Caspian Sea and the southern Urals before visiting the Altai Mountains of Mongolia and finally reaching Lake Baikal. For a while they travelled around the mountains of Transbaikalia, beyond the lake, before turning back to St. Petersburg via the Caspian and lower Volga. In 1774 they returned with a wealth of plant, animal and mineral specimens as well as ethnographic and geographic data, and the reports Pallas had sent throughout his journey were compiled into the three volume Reise durch verschiedene Provinzen des Russischen Reichs (A journey through various provinces of the Russian Empire), published between 1771 and 1776.

The success of this expedition made him a favourite of the Empress Catherine and Pallas taught natural history to her sons, the future Emperor Alexander I and his brother. Consulting his own specimens and those collected by other naturalists in Russia, Pallas began to produce his Flora Rossica, replete with descriptions and impressive illustrations for 283 species. His work can be considered the first real flora of Russia, although it was never completed; volume one parts one (1784) and two (1788) were published in his life-time and the second volume in 1815. He also started work on a zoological equivalent, but in 1793 was called to travel south to the Caucasus on a second expedition, this time in the company of his second wife and daughter.

Travelling down the Volga to the Caspian Sea, Pallas explored the northern Caucasus on his way to Crimea. He and his wife enjoyed this area very much and, after returning home up the Dnieper, Catherine II gave them several estates in Crimea. They moved in 1795 and were based in Simferopol for 15 years. Pallas continued to study the natural history of this region, developed gardens and vineyards and published a steady stream of articles (including an account of his second expedition). After the death of his wife in 1810, he requested permission to leave Russian service and return to Berlin, hoping it would hasten the completion of his zoological volumes, but his health quickly deteriorated. Fortunately, the first copy of his Zoographia Rosso-Asiatica was presented to him just months before his death (1811), although his artist G.H. Geissler was unable to complete the illustrations in time for publication. 50 plates were published much later in 1831, along with most of the original drawings.

By the end of his life Pallas had produced 170 publications; in addition to his main works, can be found monographs of a variety of plant and animal taxa, including antelopes, rodents, buntings, plant genera Spiraea L. and Astragalus L., and many others. In his work he took a holistic approach to the study of natural history and was an early scholar of comparative anatomy. Perhaps the first to publish on the relationships between different plants and animals displayed visually in the form of a tree, he was, however, a firm believer that all organisms arose at one time and that variation was in no way related to environment. The common names of a dozen or so Central Asian animals bear witness to his discoveries, including Pallas's cat, Pallas's fish-eagle and Pallas's warbler. The plant genus Pallasia was named for him by Linnaeus and his name is also commemorated in the iron-based meteorite metal Pallasite and a volcano in the Kiril Islands.

The herbarium of Professor Pallas was broken up, sold by public auction at London in May 1808, part being purchased by A.B. Lambert including many types. Numerous specimens from Pallas are now at BM originating from various sources. Pallas and Banks corresponded and Banks sent specimens to Pallas, presumably receiving material in return. Banks' herbarium was bequeathed to his librarian, Robert Brown, in 1820 and subsequently donated to BM in 1827. Some material was acquired with the herbarium of K.M.E. von Moll, purchased in 1816. During the sale of the herbarium of A.B. Lambert in 1842, types from the publications of Pallas were also purchased by BM. The Pallas herbarium contained collections of many contemporary botanists including Joseph Banks, J.R. Forster, J.G. Georgi, C. Merck, G.W. Steller and C.P. Thunberg.

Sources:
V.A. Esakov, 1974, "Pallas, Peter Simon", Dictionary of Scientific Biography, 10: 283-285
S.G. Shetler, 1967, The Komarov Botanical Institute: 44
E.C. Smith, 1941, "P.S. Pallas", Nature, 148: 334-335
F.A. Stafleu and R.S. Cowan, 1976-1998, Taxonomic Literature, 2nd edition (TL-2)
A.C. Sytin, 1999, Peter Simon Pallas's (1741-1811) Botanical and Zoological Collections and Drawings, Moscow State University:
http://herba.msu.ru/journals/Herba/12/pallas.htm, accessed 1 December 2010.