176 SCIENTIFIC LABORS OF EDWARD LARTET. 



The coinpositiou of the teeth is also not the same. Cortical or cement 

 was wanting in those of the ruminants of Sansan, although found in 

 the teeth of the fossil ruminants of Auvergne, most of which are more 

 recent. 



These ingenious researches of M. Lartet formed the germ of a work 

 which appeared in 1868, in which he laid still more stress upon the dif- 

 ferences between the fossils of the same genus of successive geological 

 periods in regard to the structure of the teeth and the size of the 

 brain. 



In 1839 M. Lartet published his first summary of the discoveries in 

 geology and paleontology in the department of Gers, with an appendix, 

 in which were described forty-foiu^ species of fossil vertebrates. Another 

 article, published in 1851, under the title, ^^Description of the Hill of 

 Sansan,^^ was exclusively devoted to the paleontological examination of 

 tb is locality, and of the other fossiliferous deposits o f Gers. The author, in 

 order to explain the richness of the fauna, and the profusion of bones 

 Ibund, supposes that a lake existed at Sansan in which the lacustrine mol- 

 luscs lived, and into which the vertebrates were thrown after their death. 

 He shows that gTcat difference exists between the fossil and the li^'ing 

 fauna of Sansan, and will not admit that the existing animals descended 

 directly from the miocene animals reconstructed by himself. Finally, 

 he gives a complete list of all the vertebrates he collected, with the ad- 

 dition of a catalogue of the terrestrial and lacustrine molluscs described 

 by Saint Ange of Boissy, Noulet, and the Abbe Dupuy. 



This list, after its publication, was modified to suit the changes in 

 nomenclature, and then confided to M. D'Archiac, to be inserted in his 

 report on tbe Paleontology of France, (1868, j). 360.) The fauna of 

 Sansan comprises seventy-one mammals, rej)resenting thirty-nine gen- 

 era, eighteen birds belonging to twelve genera, twenty-eight or thirty 

 reptiles, a few fishes, and forty molluscs of twelve genera, the largest 

 collection of vertebrates in our country ; and very few localities in the 

 world could show a similar accumulation of animals in as limited a space. 

 - In 1845 M. Lartet sent a synopsis of his recent discoveries at Sansan to 

 the Institute. "About 8,000 or 10,000 remains have been collected, 

 among them the bones of a large fossil edentate or Macrotheritim, and 

 enough parts of a dinotherium to con\ance naturalists tbat this ani- 

 mal is not cetaceous, but rather a terrestrial quadruped. There is 

 not a single species identical with existing forms. This special point 

 on the earth's surface known as Sansan, has, it seems, given birth to a 

 variety of mammals much greater than that now existing. Every de- 

 gTee in the animal scale has been here represented, including the 

 monkey. A still higher type — that of man — it is true, has not been 

 found ; but because he is wanting in these ancient formations we need 

 not conclude that he did not exist." 



These ideas in regard to the fossil man were singularly in advance of 

 the age in 1815. It almost seems as if M. Lartet had a presentiment of 



