Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/358

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Haute-Marne.; Still later M. Lory showed that the relations between the Rhodanien and the Urgonien were quite as close as those between the former and the Aptien. As we thus appear to have in the Rhodanien a complete link between the Upper and Middle Neocomian, the boundary between these divisions becomes a perfectly arbitrary one, and great diversity of opinion exists among geologists to which of them certain deposits should be assigned. Among those strata which lie upon the debatable confines of the Upper and Middle Neocomian, we must class the Punfield Formation. But though there may be diversity of opinion as to the artificial scheme of classification best adapted for grouping these strata, their true relative position in the Neocomian series is on palaeontological evidence perfectly clear. Ammonites Deshayesii, which occurs in the Marine Band of Punfield, is a very widely distributed species and has a restricted and well-defined vertical range, abounding in the higher portions of the Neocomian, but being unknown in the Urgonien or any lower bed. Vicarya Lujani and several other of the Punfield shells are well-known and characteristic Rhodanien forms. All the palaeontological evidence points to the confines of the Upper and Middle Neocomian as the true place of the Punfield formation ; and it will, I think, be in accordance with the views of a majority of the geologists of authority on this subject to regard the " Perna-beds " as the base of the Upper Neocomian, and the Punfield beds as the highest part of the Middle Neocomian.

2. Coal-bearing Strata of Eastern Spain. — It is, however, in the Spanish peninsula that we find the closest analogues of the Punfield Formation. These beds have, during the last twenty years, been made known to us by the admirable researches of MM. Vilanova, de Verneuil, Collomb, de Loriere, and Coquand. As no description of these beds has yet appeared in this country, it may be of interest to notice briefly their chief features in this place. The recently published very valuable memoir of M. Coquand enables us to do this the more readily*.

The principal exposures of the deposits in question are situated on the confines of the ancient kingdoms of Arragon and Valencia, in the provinces of Teruel and Castellon de la Plana, though less important and outlying masses of the same strata occur in the valley of the Guadalupe and in Catalonia, near the mouth of the Ebro.

In the province of Teruel, where they form three important productive coal-basins, those of Utrillas, Gargallo, and of the Val d'Arino, the strata, which are more than 1600 feet thick, are divisible into three series, which, however, pass into one another

  • De Verneuil et Collomb. Bull. Soc. Geol. de France, 2e ser. tome x. (1853).

Vilanova, Memoria Geognostica (1859).

H. Coquand. Mem. de l'etage Aptien de l'Espagne (1865).

De Verneuil et De Loriere. Fossiles d'Utrillas (1868).

De Verneuil et Collomb. Carte geologique de l'Espagne et du Portugal (Paris 1864).

H. Coquand. Description geologique de la formation cretacee de la province de Teruel. Bull. Soc. Geol. de France, 2me ser. tome xxiv. p. 144 (1868).