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GEOLOGICAL MEMOIRS. 



That gentleman had lately visited this spot, and most obligingly 

 lent them the map of the Quarter-master-generaFs staff, which he had 

 employed on his route, and which contains a vast quantity of original 

 unpublished observations. From Gloggnitz the road leads over St. 

 Christoph behind the Grillenberg up to the steep declivity of the 

 Johannsberg. Traces of fossils are soon observed, which are most nu- 

 merous south of the Gahnsbauer, a house lately burnt down. Here 

 there is a small plateau with very steep sides towards the valley, 

 throughout which the rock is everywhere observable, although much 

 overgrown with trees. The most important organic remains are the 

 following : — 



Gryphcea Columba, Lam. 



Ostrcea serrata, Defr. 



Hemipneuster radiatus, Agass. Only the flat under side with 

 small fragments of the sides are preserved. The very distinct chan- 

 nels running down from the apex to the mouth, as well as the general 

 appearance, seem to make this identification certain. 



Inoceramus ; in small fragments. The determination of this genus 

 rests upon the fibrous structure of the fractured surface. 



Terebratula ; several species, not determinable. 



Hippurites ; a fragment, not determinable. 



Ostrcea, or Gryphcea ; fragments of a large species, not deter- 

 minable. 



Together with these species, and sometimes in the same hand spe- 

 cimens, occur numbers of lenticular bodies, which bear so close a 

 resemblance to Nummulites, that they were only distinguished by a 

 close examination in the cabinet. The interior does not exhibit the 

 regular spirally-arranged chambers of Nummulites, but cells irregu- 

 larly or at least not spirally disposed, exactly as in the Lycophris of 

 the chalk tuff of St. Peter's Mountain, near Maestrieht. Some natu- 

 ralists, it is true, have united the Nummulites with Lycophris and 

 Orbitulites* {Orbitoides^ ; yet thewant of a spiral arrangement of the 

 cells in the two latter seems to afford a good character on which to 

 found a separation. The Lycophris of Gahnsbauer sometimes exceed 

 an inch in diameter ; they occur in the rock in precisely the same 

 abundance as Nummulites do, and might therefore readily cause these 

 beds of the age of the chalk to be confounded with the eocene 

 nummulitic formations. 



The above fossils are found in a reddish calcareous sandstone, 

 which on being dissolved in an acid leaves a considerable residue of 

 quartzose sand. 



Though well-exhibited to great heights, no traces of bedding can 

 be seen in it. 



Opposite the Gahnsbauer, N.E. of Priiglitz, a second locality where 

 the Orbitulite sandstone shows itself, was examined. Here, as far as 

 the eye could judge, it rose to the same height above the valley as at 



* [With regard to the true foraminiferous character of this genus and that of 

 Orbitoides, with which possibly it is here confounded, and their relations to Num- 

 mulites, see Dr. Carpenter's Paper on the Structure of Nummulites, Orbitolites f 

 and Orbitoides, Quart. Journ. Geol. Soc. vol. vi. p. 21 et seq. — Ed.] 



