( -^27 ) 



fossils have been frequently met with. We tind them already men- 

 tioned by J. T. BiNKHORST VAX DEN BlNKHORST ^). 



Fr. Seghers discovered a Rhynchonella and part of an Ammonites 

 at Genck '). Close to this place, at Gelieren, E. Dei.vaux frequently 

 came across remains of "calcaire a Chailles" '). C. Malaise gave a 

 description of petrified Nerinea found at Rothem and an Isastraea at 

 Jambes, near Namur ^). A. Erexs mentions a few other fossils ') and 

 finally we have an account of a yellow oolite, discovered by E. van 

 den Broeck among the erratics of the Meuse, and here we call 

 attention to the peculiar siliceous oolites scattered About the plateau of 

 the JMeuse and which probably belong to the Jurassic system '). As 

 yet no trace of similar oolites has been discovered North of the Rhine, 

 but J. LoRiÉ noticed some in the borings of a well at Mariendaal, 

 near Grave "). A few weeks ago Mr. L. Rutten found a small pebble 

 in the diluvium at KoUenberg, near Sittard. 



Tertiary system. [Eocene). Very interesting are the accounts of 

 the discovery of erratics comprising specimens oï Numniulma laevigata 

 Lam. Ferd. Roemer has given a description of a fragment of this 

 kind derived from Holten, in Overijsel, but believed it to have only 

 accidentally found its way among the erratics '). Staring made 

 mention of a couple of rounded-off pieces of hornstone, one of which 

 had been found on the rising ground of Hellendoorn and the other 

 on the Steenshul, near Oldebroek, and which he referred to the Alps? 

 "If we did not know the place where these specimens were obtained, 

 "we should be rather inclined to think they came from a collection 

 "in which the objects had been confused and believe these rocks to 



') Esquisse géologique el paluontologique de.s couches crétacées du Lirabourg. 

 Maastricht 1859. p. 7. 



-j Ann. de la Soc. malacolog. de Belgique X. Bruxelles 1875. Bull. p. XXXIV. 



•'') Les anciens depots de transport de la Meuse, appartenant a I'assise raoséenne 

 observes dans les ballastiéres de Gelieren prés Genck en Campine. Bull. Soc. 

 géolog. de Belgique XIV. 1886/87. Liége. 1887. Mém. p. 102. 



*) Sur quelques fossiles du diluvium. Ann. Soc. malacolog. de Belgique X. 

 Bruxelles 1875. Bull. p. IV. 



■i) Note sur les roches cristallines 1. c. p. 413. 



'') E. VAN DEN Broeck. Lcs callloux oolithiques des graviers tertiaires des hauts 

 plateaux de la Meuse. Bull. Soc. beige de Geologie III. Bruxelles 1890 p. 404—412. 



X. Stainieb, Origine des cailloux oolithiques des couches a cailloux blancs du 

 bassin de la Meuse. Ann. Soc. géolog. de Belgique XVIII. 1890—92, p. CV, 92. 



E. VAN DEN Broeck. Coup d'oeil synthétique sur l'Oligocène beige. Bull. Soc. beige 

 de Geologic VII. Bruxelles 1893 p. 25, 26<i. 



"') Beschrijving van eenige nieuwe grondboringen, Verhandel. K. Akademie v. W. 

 2de sectie. VI, N. 6. Amsterdam 1899, p. 33. 



^) Ueber Hoilandisclie Diluvial-Geschiebc. Neaes Jabrb. f. Min. 1857, p. 392, 



37 



Proceedings Royal Acad. Amsterdam. Vol. VIII. 



