96 M. de la Jonkaire on the Geology of Ant-iUerp. 



coloured by iron, containing a great quantity of those green 

 grains so common in the lower part of the calcaive grossier, 

 which are the silicate of iron of M. Berthier. I have only 

 collected the following fossil shells ; they are doubtless far from 

 being the whole of those here found, yet their enumeration 

 may be useful in determining the formation containing them. 



Astarte. 4 or 5 undetermined 



Turritella triplicata. 



tornata. 



Natica. 



Ostrea. 

 Pecten plebeius. 



4 undescribed species. 



Pectunculus pulvinahis. 



niimmiformis. 



species. 

 Isocardia Cor. 

 Cardium. 



Lucina circinnata. 

 Venus. 2 uiidescribed species. 

 Cyprina islandicoidcs. 



another species. 



Numviulites. 



Astarte obliquata. 



" Fragments of silicified fossil wood, which appear to be- 

 long to genera approaching the Pahns. 



" Having enumerated the beds seen at Antwerp, we shall 

 now endeavour to refer each to its equivalent of the environs ot 

 Paris. 



" The Lotsoer Clay. — The lowest clay bed, that which we first 

 mentioned, appears to contain shells ; but notwithstanding all 

 our efforts we were unable to procure any, consequently we 

 are unable positively to determine its equivalent. Neverthe- 

 less, if what we advance respecting the following beds shall 

 be confirmed, it can only belong to the plastic clay, which 

 in many places, even in the Paris basin, contains beds that 

 would appear to be charged with shells. 



" TJie Second Clay. — The following bed, though still not well 

 characterized, is however more so by its mineral structure, 

 its predominant colour, so often shown in the plastic clay, and 

 by its lignite, which seems to occur at a short distance, and in 

 a similar position. 



" In fact, strata which appear to be the continuation of those 

 we are describing, and which represent them in other points 

 of the Pays-Bas, contain beds of bituminous clay, and even 

 true lignites. Of these are the lands of Huisduinen, and pro- 

 bably the pretended peat containing the cocoa and areca nuts 

 figured by Burtin. It should be remarked on this head that 

 we should mistrust this term peat, as applied so generally in 

 Holland to all those places from whence a combustible sub- 

 stance is extracted ; for it certainly is not in peat properly so 

 called, that we should meet with a mixture of fresh-water and 

 marine shells, or with amber. Now these are found in the 

 pretended peat, and particularly the amber, which has become 



