349 'I'he Oligocene of the Southern United States 39 



however, pra<5iically no mention of fossils. Grateloup,* from 

 1834-40, described a large number of species from the Adour 

 marls. In the publication in 1840,! in which he figures the 

 species previoush' described, he notes the Yellow, Blue and 

 White marls of the Adour valley, and refers the White to the 

 Eocene (calcaire grossier) of the Paris basin, the Blue to the 

 lower Miocene and the Yellow to the upper Miocene. In 1855, 

 Delbos'l correlated the White marls and the Adour limestone, 

 ■which are both chara<5lerized by Natica crassatina^ and a portion 

 of the Blue marls with the Asterias limestone of the Gironde 

 valley and with the Fontainebleau sands, 



Hebert|] found further proofs of the parallelism of the 

 Adour marls, with Natica cyassatina, and the Fontainebleau sands. 



Nummulites in the Blue marls. Toumouer^ called attention, 

 in 1863, to the remarkable abundance of Nummulites, especially 

 the species intermedia, in the Blue marls of the Adour valley. 

 This is of interest as compared with their rarity in the neighbor- 

 ing valley of the Garonne and with their abundance in the 

 northern Italian basins. 



Affinities of the A dotir fauna. In general, the fauna of the 

 Oligocene of the Adour is, like that of the Gironde, more closely 

 allied to the species of the Italian deposits, and has but few forms 

 in common with the equivalent beds of the Paris basin. 



Oligocene of the Ceyitral Plateau. Both lower and Upper 

 Oligocene are developed in the southeastern part of the Plateau. 



* Tableau des coquilles fossiles des terrains tertiaires des environs de 

 Dax, ARes de la Sac. Linn, de Bordeaux, t. VI-VIII; Monographies des 

 coquilles tertiaires du bassin de 1' Adour, Ibid., t. X, 1838, et t. XI, 1840. 



\ Conchy. Fossile des Terr. Tert. du Bassin de TAdonr, Atlas, 1840. 



X Notice geol. sur les terr. du bassin de 1' Adour, BtUl. de la Soc. Geol. 

 de Fr., 2eme ser., t. IV, p. 712, 1847; Essai d'une desc. g^ol. du bassin de 

 I'Adour, Man. des Set. phys. et nat, de Bordeaux, t. I, Jan., 1855; Notice 

 sur les faluns du sud-ouest de la France, Bull, de la Soc. gM. de France, 

 2eme ser., t. V, p. 417, 1848. 



II Bull. Soc. Geol. Fr., 2eme s6r., t. VI. p. 466, 1849. 



\ Note sur la presence des Nummulites dans I'^tage a Natica crassatina 

 du bassin de I'Adour, Bull. Soc. Geol. de Fr., t. XX, 2eme ser., 1S62-3, p. 649. 



