( o26 ) 



feroLis limestone in a gnu'el pit at Gelieren near Genck ') and J. 

 LoRiÉ at Smeermaes and Lancklaer, on the Zuid-Willems canal. 



The original home of these various limestones cannot be determined 

 with any certainty. However, as numerous layers of crinoidal lime- 

 stone are present in tlie districts of Aix-la-Chapelle and Stolberg") 

 as well as in the valley of the Meuse, more especially near Dinant, 

 it seems rational that we should in the lirst place look to these parts 

 for their origin "). In any case they must have been transported 

 along the Meuse, for tlie district Aix-la-Chapelle — Stolberg is drained 

 by the Geul, tlie Inde and the Worm, which all three flow into 

 the Meuse. 



Finally Rokmer gi^es in his treatise a description of fragments of 

 plitlianite, found near Ootmarsum, in Overijsel, which he thinks 

 derived from the layers of culm on the lower Rhine. This conjecture 

 is not inadmissible, but at the same time the tact must not be 

 overlooked that this kind of rock is also plentifid in the valley of 

 the Meuse. 



Jurassic System {Ox/ordian). In the foregoing pages mention has 

 already been made of a piece of brownisii yellow sandy clay, found 

 by J. LoRiÉ on the Wageninger hill (Guelders) in whicli was inbedded 

 a perfect specimen of Rhynehonella Thurmaiuii ^'oltz, in every respect 

 similar to the fossils of this species found at Vieil-Saint-Rémy, to the 

 South-West of Mézières in the department of the xlrdennes *). This 

 is the oidy fossil of this type discovered in oiir country, although 

 in the dibivium of Sonlli Limboui'g and Norlheni Helgium, Jurassic 



1) Les anciens depots de transport de la Meuse, appartenant a I'assisc; moséenne 

 observes dans les ballastieres de Gelieren pres Genck on Gampine. Ann. Soc. géol. 

 de Belgique XIV. 1886—87. Liége 1887, Mém. p. 103. 



Here again, as at Maarn, he ascribed their presence to an "accident". 



-) J. Beissel. Ueber Struktur und Zusammensetzung des Kohlenkalks in der 

 Umgebung von Aachen. Verhandl. natiuh. Yereins Rheinl. u. Westf. XXXIX. Bonn 

 1882. Corresp. Bl. p. 92. 



*) Ed. Dupont. Notice sur les gites de fossiles du calcaire des bandes carboniféres 

 de Flourens el de Dinant. Bull. Acad. roy. de Belgique (2) XII Bruxelles 1861 p. 293. 



Ed. Dupont. Essai d'une carte géologique des environs de Dinanl 1. e. (2) XX. 

 1865. p. 621, 622, 629. 



Ed. Dopont. Carle géologique des environs de Dinant. Buil. Soc. geol. de Fr. (2) 

 XXIV. Paris 1866-67 p. 672, 673. 



Ed. Dupo.nt et Michel Mourlon, Explication de la feuille de Dinanl. Musée d'hist. 

 nat. de Belgique. Service de la carte géolog. du Hoyaumc. Bruxelles 1883, p. 9, 

 26, 33, 34, 53 et passim. 



*) Contributions .i la gciilogie dos Pays-Bas-. Archives Tcyler (2) III. Haarlem 

 1887, p. 10. 



