Great Geologists | 45
and then La Rochelle itself in 1820. His father was a doctor
and a keen amateur naturalist. From an early age, Alcide and
his brother Charles accompanied their father on shell-collecting
trips on the French Atlantic coast and Alcide began to sketch
their finds with a talent for drawing that would subsequently
typify his career. Alcide was only 11 years old when he began
to examine foraminifera found in the local beach sands, soon
supplemented by material sent to his father from Rimini and
Corsica and later from around the world. These often beautifully
shaped and complex microscopic shells both in living and in
fossil form became a subject of special interest to him and by
1825 he was able to use the term Foraminifera for the first time to
describe them, although mistakenly regarding them as tiny forms
of cephalopod (their true biological affinities, single-celled protists,
was determined by Félix Dujardin in 1835). d’Orbigny’s “Tableau
méthodique de la classe des Céphalopodes” presented to the
Académie des Sciences in November 1825 enumerated, for the
first time, the various taxa he recognized within the foraminifera,
along with detailed descriptions of their morphology and mode
of life. Both modern and fossil forms were documented and
classified. He also made physical models of many species of
foraminifera, enlarged 40–200 times, so that their features could
be more easily observed. After carving the scaled-up versions out
of gypsum, he made plaster replicas which were distributed to
universities and museums. Many modern institutions still house
collections of d’Orbigny’s foraminifera models.
His work soon attracted the interest of the scientific establishment
in France which in turn led him being asked to undertake an
expedition to South America. Consequently, from June 1826
to March 1834 his travels encompassed the lands from the
southern tip of the American continent to the mountains of Bolivia
and Peru and much in-between. He collected a vast amount of
material and the results of the expedition were published in nine
volumes accompanied by around 500 plates. 160 mammals,
860 birds, 115 reptiles, 166 fish, 980 molluscs and zoophytes,
5000 insects and crustaceans and 3000 plants were collected
and described, many new to science. The stratigraphical geology
of the South American continent was described, supported by
palaeontological descriptions. He produced the first geographical
and geological maps of Bolivia. His study of the native peoples in
South America led to a complete treatise on anthropology. The list
of achievements of his participation in this expedition is immense.
Nor were his travels without adventure. He passed an unfortunate
15 days of his long trip in a Uruguayan prison (“a putrid hole full of
malefactors and chained murderers”) after local soldiers found his
barometer suspicious.
Alcide d’Orbigny from a lithograph by Lavallée (1839).
The efforts required to document his South American expedition
did not deter him from expanding his research into new spheres
and in particular the geological record. His first publication on this
theme in 1839 was to describe the foraminifera of the Cretaceous
Chalk. This included the recognition of fifty new species, but
moreover, he surmised that during the Cretaceous period the Paris
Basin had been invaded by a warm sea lacking strong currents – a
pioneering attempt at using microfossils for paleoenvironmental
purposes and to recognize transgression. Following on from this
study he undertook the immense task of describing all species
of fossil invertebrates found in France in the eight volumes of “La
Paléontologie française”, a work that remained incomplete at the
time of his death.