ON THE TERTIARY FORMATIONS OF SPAIN. 7 



sake of greater convenience, although not representing distinct 

 periods. 



I. The first group contains the hills in which the village of Concud 

 is situated, north-west from Teruel. It consists of beds of gypsum 

 white or reddish, crystalline or compact, without any fossil remains ; 

 of a bed of dark vegetable soil resembling dried mud containing nu- 

 merous bones of mammifers, viz. the ox, hyaena, horse, &c., with their 

 teeth, the bones and molar teeth of mastodons, and the incisor teeth 

 of a large ruminant. The bones are well-preserved, the medullary 

 canal is sometimes filled with calcareous spar. The teeth are in still 

 better preservation, but the large ones fall to pieces on coming in 

 contact with the air. Below this bed is another 40 or 50 varas in 

 thickness, of reddish or brown gypsum, showing in many places an 

 efflorescence of sulphate of soda, and containing a new mineral which 

 the author calls Teruelite, supposing it to be a carbonate of lime and 

 iron. Prof. Breithaupt afterwards considered it as a variety of Bitter- 

 spar analogous to what he had found in the gypsum of the salt-mines 

 of Tyrol called Braunerite. Its chief locality is the neighbourhood 

 of Teruel. Below this gypsum are beds of calcaire grossier contain- 

 ing many freshwater fossils in excellent preservation, particularly the 

 Limnsei and Planorbes, which, on being extracted, look as if they 

 had been only recently deposited. These beds rest on calcareous 

 sands and conglomerates without fossils. 



II. The second group consists of almost horizontal beds of a 

 yellow siliceous limestone full of the same freshwater fossils com- 

 pletely petrified ; conglomerates and yellow sands in thick beds with 

 few fossils again succeeded by siliceous limestones. This group may 

 be traced for about six hours down the banks of the river Guadala- 

 viar, which flows out of the above-mentioned lacustrine plain. 



III. The third group is best seen between the heights of Morron 

 de la Nava and Ademuz. The following is the series of beds in de- 

 scending order : — 



1 . A yellow hard siliceous limestone with conchoidal fracture con- 

 taining Planorbis and Paludina. 



2. Compact reddish-brown gypsum. 



3. Siliceous limestone with Planorbis and Paludina, giving out a 

 foetid odour when rubbed, in consequence of its containing sulphur. 



4. Black limestone, hard and foetid from the same cause. 



5. Compact gypsum, white or reddish-brown. 



6. Calcaire grossier, white and earthy, with the same fossils. 



7. Gypseous marl, bituminous and dark -coloured, with crystals of 

 gypsum and carbonized vegetable remains. 



8. Specular and fibrous gypsum. 



9. Sulphur. 



10. Grey bituminous gypseous marl. 



11. Calcaire grossier with fossils. 



The first six beds form a thickness of about 80 varas ; the seventh, 

 called in the country piedra de encovar'^, has a thickness of 1 or IJ 

 vara, and serves as a sure guide to the miners in searching for the 

 * Encovar, to put anything into a cellar, to lay up in a cellar. 



