164 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Nov. 21, 



The limestone of Mealhada is slightly exposed and its relations are 

 not well seen : on the north and south it is soon covered up hy the 

 subcretaceous sands, but I did not see how far it extended in the other 

 directions. 



Li?neston€ of San Pedro and Shale of Ramalhao, near Cintra. 



These beds are described at p. 122 of my former paper on the 

 Neighbourhood of Lisbon, where they are erroneously stated to be 

 continued to the coast along the north side of the range of granite : 

 this is not the case, as on that side of the hills they stop close to the 

 town of Cintra, and the beds which overlie the granite between Cintra 

 and the sea belong to the subcretaceous series. 



In the shale at Ramalhao some organic remains occur, but usually 

 in very bad condition, as the great masses of trap interstratified with 

 the shale have altered its characters and almost reduced it to the con- 

 dition of slate : the following were found by the side of the road close 

 to Ramalhao : — 



Ammonites, too much crushed Avicula, 



for identification. Posidonia Bronnii, Goldf. t. 113. f. 7. 



Pleurotomaria. 



The last is a species found in the has of Wirtemburg, with which for- 

 mation we must connect this bed until we have better evidence re- 

 specting it. 



I have nothing to add to the former description of the San Pedro 

 limestone ; the only organic remains observed in it were amorphous 

 masses apparently related to sponges, which are very abundant in the 

 limestone a httle to the north of San Pedro. The shells mentioned 

 at p. 123 of the former paper belong to the subcretaceous limestones. 



As the shale of Ramalhao overlies the San Pedro hmestone con- 

 formably, it is probable that the latter also belongs to the period of 

 the lias. 



The preceding rocks are all the deposits north of the Tagus be- 

 longing to the oohtic series with which I am acquainted. I beheve 

 that the high limestone range of the Serra de Arrabida near St. Ubes 

 will also prove to belong to the same series : but the limestone hills 

 along the coast between Coimbra and Cape Espichel, formerly de- 

 scribed as the Espichel limestone, belong with the rest of that forma- 

 tion to the subcretaceous series. (See ante p. 151, and Geology of 

 Neighbourhood of Lisbon, p. 121.) 



The preceding descriptions of the various isolated jm-assic deposits 

 of Portugal, coupled with the study of the organic remains contained 

 in them, lead to the following comparison of these rocks with the 

 oohtic series of England, viz. : — 



The hmestone of Monte Junto and subjacent sandstone are to be 

 classed with the upper portion of the oolites. 



The limestone of Coimbra, resting on a great thickness of red sands, 

 will probably prove next to the above in the descending order. 



The calcareous beds above the coal of Cape Mondego, surmounted 

 by red sandstone, belong to the middle of the oolitic series. 



