By Richard Fariña, Sebastián Tambusso and Luciano Varela, UdelaR
Formed in the highly prestigious school of medicine in Paris, Teodoro Vilardebó must have experienced great concern when the cruel symptoms of the yellow fever he was all too familiar with when treating his patients were observed in himself. What must have been his worst fears were sadly confirmed: Vilardebó died in March of 1857, leaving a tremendous legacy as a physician, politician, compiler of words in native languages and, among other aspects of his ingenuity, as a palaeontologist and fossil merchant.
Precisely, this latter activity turns out of our interest, since he happened to have been involved in selling to the Muséum national d’Histoire naturelle in Paris a fine collection of South American (mostly Argentinian) fossils of the impressive Pleistocene megafauna, an assemblage of giant mammals that includes glyptodonts, ground sloths, sabretoothed felids and many other very large species.
Another person of importance was François Séguin, referred in some documents as a confectioner in Buenos Aires, but an adventurous collector (and, most importantly, fossil vendor as well) that deserves more attention than traditionally assigned.
Both collectors had their fossils sold to the MNHN and many important specimens are highlighted here as examples of the treasures of the past that, having been found in the then new republics of the Plata along the 19th century, moved to one of the centres of intellectual endeavours in Europe. Among many other examples, we analysed the following material in our visit of April 2022 to that venerable institution, cradle of the vertebrate palaeontology and comparative anatomy. As can be seen in the photos, the fossils are diversely labelled and conserved, the hallmark of the changes in techniques and criteria over the past decades, even centuries.

A nearly complete skeleton of the ground sloth Glossotherium (actually, the type species of today’s synonymised genus Pleurolestodon) from the Vilardebó’s collection was carefully photographed with the aim of digitally reconstructing it. The technique used, called photogrammetry, consists in taking pictures of an object from many different angles to make a digital 3D model that can also be physically printed or reproduced otherwise.


Other materials from Uruguay are found in the collections of the MNHN (but not necessarily collected by the people mentioned above), a cast of glyptodont osteoderms was donated by the great Argentinian palaeontologist Florentino Ameghino, revealing the tight network of fossil travelling of the time.


Also of interest, especially for those that study fossils, some fragments of the caudal sheath of Panochthus nodotianus, a no longer valid species created by Ameghino in 1889, were observed. Surprisingly enough one of the pieces seems not to belong with the two others, according to their preservational characteristics, a subject we might want to further study in the future.

Other fragments, possibly collected by Vilardebó in Uruguay, of the impressive armour of a glyptodont show a curious story: kept under the code PAM 216 to 218, they are referred to as the type of Boreostracon and corrected as Hoplophorus. However, the figures in the publication that describes those remains show a rather different material.



Further curiosities are the skull of a juvenile ground sloth Scelidotherium, originally lacking the skull roof and the snout, reconstructed as that of an armadillo. Despite the donations and purchases of cast is nowadays as frequent as in those times, there are several specimens labelled as from “Museo de La Plata” but with no indication of them having been donated or sold.

Finally, the type of the giant sloth Lestodon armatus, from the Vilardebó collection, is mentioned by the French palaeontologist Paul Gervais in the publication that created it in 1855 as having only one mandibular ramus, but the specimen has the two rami artificially glued together. It can be speculated that the second ramus was found after the material was published in some of the boxes of the Vilardebó collection and it was noted to belong to the same individual. Further research in the yet undigitised archives might shed light on this subject.


In another publication from 1873, more material from Séguin’s collection was added to the description of Lestodon armatus. Found together with them, there is a hip fragment that, due to their size, might belong actually to a smaller ground sloth, perhaps Glossotherium robustum. The hip was mounted on display along with the complete leg for a century and all these elements were taken down a couple of years ago.

Further reading:
- Podgorny I. 2001. El camino de los fósiles: las colecciones de mamíferos pampeanos en los museos franceses e ingleses del siglo XIX. Asclepio 53: 97-116.
- Podgorny I. 2011. Mercaderes del pasado: Teodoro Vilardebó, Pedro de Angelis y el comercio de huesos y documentos en el Río de la Plata, 1830-1850. Circumscribere9: 29-77.