366 Brigadier Silvertop's Sketch of the Tertiary Formation 

 that now existing in the Mediterranean, and many fragments of 

 Ostrea. No vegetable or animal remains could be discovered, 

 nor, as I was informed, had any such been found at this loca- 

 lity. 



Part of the town of Malaga is built upon this argillaceous 

 deposit, through which wells are sunk into a subjacent bed of 

 sand, where water is found. 



This member of the tertiary may also be seen in some escarp- 

 ments on the left bank of the Guadamedina, which, as above 

 stated, bounds the little tract under consideration towards the 

 west ; and two miles up this stream from Malaga, there is a con- 

 siderable patch of it, in which vertebral bones (probably of the 

 Delphinus, as will afterwards be seen) were discovered in making 

 an excavation for a pond. 



On the left bank of the Guadamedina, I have not observed this 

 argillaceous bed at any other point. The remaining higher un- 

 dulating ground of the little tract immediately under considera- 

 tion, belongs to the tertiary beds of group 2d, (see sect. 1. PL II.) 

 But, on the opposite or western bank of this stream, it is exten- 

 sively developed over an open, hilly, ravined tract that borders 

 the mountainous country towards the north, and terminates 

 southwards in a large horizontal flat, along the Mediterranean 

 shore, between Malaga and Churiana. From this tract, which 

 may be stated to be enclosed by the Guadamedina and Guadal- 

 horce rivers, it may be followed, in an irregular manner, for six- 

 teen miles up the estuary or Valley of Malaga, to a village called 

 Alaurin el Grande, where, in consequence of its being worked 

 for brick-earth, another fine opportunity is presented of observ- 

 ing the organic remains that have been entombed in its mass. 

 (See sect. % PI. II.) 



Alaurin el Grande, a remarkably neat clean little village, sur- 

 rounded by orchards of fruit-trees, is situated at the base of the 

 Sierra de Mijas, which bounds the Valley of Malaga towards the 

 W. S. W., and contiguous to the village, which is about eighteen 

 miles distant from Malaga, and, between 900 and 1000 feet 

 above the level of the Mediterranean, there is a small tract on 

 the slope of the adjoining mountain-ridge to the valley, where 

 the excavations for brick-earth, just alluded to, have been made. 

 The workings are carried on by perpendicular shafts, generally 



