Louis Agassiz

Jean Louis Rodolphe Agassiz (May 28 1807-December 14 1873) was a Swiss-born American zoologist, glaciologist, and geologist, the husband of educator Elizabeth Cabot Cary Agassiz, and one of the first world-class American scientists. He was a prominent supporter of polygenism.

Early work

In 1819-1820, Johann Baptist von Spix and Carl Friedrich Philipp von Martius were engaged in an expedition to Brazil, and on their return to Europe, amongst other collections of natural objects they brought home an important set of the fresh water fishes of Brazil, and especially of the Amazon River. Spix, who died in 1826, did not live long enough to work out the history of these fishes, and Agassiz (though fresh out of school) was selected by Martius for this purpose. He at once threw himself into the work with an enthusiasm which characterized him to the end of his busy life. The task of describing the Brazilian fishes was completed and published in 1829. This was followed by research into the history of the fishes found in Lake Neuchâtel. Enlarging his plans, in 1830 he issued a prospectus of a History of the Freshwater Fishes of Central Europe. It was only in 1839, however, that the first part of this publication appeared, and it was completed in 1842. In 1832 he was appointed professor of natural history in the university of Neuchâtel. The fossil fishes there soon attracted his attention. The rich stores furnished by the slates of Glarus and the limestones of Monte Bolca were known at the time, but very little had been accomplished in the way of scientific study of them. Agassiz, as early as 1829, planned the publication of the work which, more than any other, laid the foundation of his world-wide fame. Five volumes of his Recherches sur les poissons fossiles ("Research on Fossil Fishes") appeared at intervals from 1833 to 1843. They were magnificently illustrated, chiefly by Joseph Dinkel. In gathering materials for this work Agassiz visited the principal museums in Europe, and meeting Cuvier in Paris, he received much encouragement and assistance from him.

Related Topics:
Johann Baptist von Spix - Carl Friedrich Philipp von Martius - Brazil - Fresh water - Fish - Amazon River - 1826 - 1829 - Lake Neuchâtel - 1830 - 1839 - 1842 - 1832 - University of Neuchâtel - Fossil - Slate - Glarus - Limestone - Monte Bolca - 1833 - 1843 - Joseph Dinkel

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Agassiz found that his palaeontological labours made necessary a new basis of ichthyological classification. The fossils rarely exhibited any traces of the soft tissues of fishes. They consisted chiefly of the teeth, scales and fins, even the bones being perfectly preserved in comparatively few instances. He therefore adopted a classification which divided fishes into four groups: Ganoids, Placoids, Cycloids and Ctenoids, based on the nature of the scales and other dermal appendages. While Agassiz did much to place the subject on a scientific basis, this classification has been superseded by later work.

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As Agassiz's descriptive work proceeded, it became obvious that it would over-tax his resources unless financial assistance could be found. The British Association came to his aid, and the earl of Ellesmere -- then Lord Francis Egerton -- gave him yet more efficient help. The 1,290 original drawings made for the work were purchased by the Earl, and presented by him to the Geological Society of London. In 1836 the Wollaston medal was awarded to Agassiz by the council of that society for his work on fossil ichthyology; and in 1838 he was elected a foreign member of the Royal Society. Meanwhile invertebrate animals engaged his attention. In 1837 he issued the "Prodrome" of a monograph on the recent and fossil Echinodermata, the first part of which appeared in 1838; in 1839-1840 he published two quarto volumes on the fossil Echinoderms of Switzerland; and in 1840-1845 he issued his Etudes critiques sur les mollusques fossiles ("Critical Studies on Fossil Mollusks").

Related Topics:
British Association - Earl of Ellesmere - Lord Francis Egerton - Geological Society of London - 1836 - Wollaston medal - 1838 - Royal Society - Invertebrate - 1837 - Echinodermata - 1840 - 1845 - Mollusk

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Before his first visit to England in 1834, the labours of Hugh Miller and other geologists brought to light the remarkable fishes of the Old Red Sandstone of the north-east of Scotland. The strange forms of the Pterichthys, the Coccosteus and other genera were then made known to geologists for the first time. They were of intense interest to Agassiz, and formed the subject of a special monograph by him published in 1844-1845: Monographie des poissons fossiles du Vieux Gres Rouge, ou Systeme Devonien (Old Red Sandstone) des Iles Britanniques et de Russie ("Monograph on Fossil Fishes of the Old Red Sandstone, or Devonian System of the British Isles and of Russia").

Related Topics:
England - 1834 - Hugh Miller - Old Red Sandstone - Scotland - Pterichthys - Coccosteus - Genera - 1844 - 1845

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In the early stages of his career in Neuchatel, Agassiz also made a name for himself as a man who could run a scientific department well. Under his care, the University of Neuchâtel soon became a leading institution for scientific inquiry.

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