S4 



PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



setting aside the improbability that masses of soft sandstone con- 

 taining still perfectly preserved casts should be drifted from any 

 known locality in Britain northwards, the point of greatest interest 

 is that the indications are not only of the near neighbourhood of some 

 members of the cretaceous formation, but actually of the " Upper 

 Greensand" itself, — a formation not known to exist further north 

 in Britain than Cambridgeshire. It is probably, however, represented 

 in Antrim*. 



There appears to me every reason to believe too, that the Green- 

 sand is in situ, occurring as it does at a low level compared with those 

 local accumulations of Chalk-flints which are described in Mr. Fer- 

 guson's memoir on the subject t- 



The following list of fossils will serve to show the geographical 

 range of the species, as well as to identify the formations. From the 

 flints of the chalk-formation we are able to add three or four inter- 

 esting fossils to the British list ; — one is the Lima elegans of Nilsson, 

 a species figured also by Hisinger. The occurrence of Crania costata, 

 Kingena lima, Spondylus striatus, Inoceramus striatus, Micraster 

 cor-anguinum, &c., leaves no doubt as to the age of the formation. 



And the presence in the Greensand of such species as Galerites 

 castanea, Area carinata. Pinna tetragona, and especially the Thetis 

 major, indicates as clearly that it is the Upper, and not the Lower, 

 Greensand, which here underlies the Chalk. Nilsson and Hisinger, 

 in their enumeration of the Cretaceous fossils of Scania, give many 

 which are characteristic of the chalk, and mention some also which 

 are from the green-sand ("arena viridi"). Amongst the former 

 the Lima {Plagiostoma) elegans belongs to the chalk of Balsberg, 

 associated with Inocerami, as in the Scottish locality. 



In the hard lower siliciferous chalk of Sweden, the Lima semisul- 

 cata, Pecten orbicularis. Sow., and the so-called P. corneus occur. 

 iVs this rests on, and passes down into Greensand full of fossils 

 (amongst others the Belemnitella mucronata), there is probably the 

 same succession on the south coast of Sweden, which we are now 

 enabled to indicate for the East of Scotland ; and the latitudes are 

 nearly the same. 



List of Fossils found in Chalk-flints from Aberdeenshire. 



\Note. + signifies the more abundant species ; — rare ones.] 



Ventriculites, several species ; fragments -\- Bogingarry, &c. 



Parasmilia centralis, Mant + Bogingarry. 



Micraster cor-anguinum, Leske -|- Bogingarry. 



Ananchytes laevis, Deluc — Bogingarry. 



Galerites (Discoidea) subuculus, Leske — Moreseat. 



Cidaris clavigera, Mant., spine and plate — Bogingarry, Cruden. 



, sp — Smallburn. 



* The collections of Mr. James M'Adam of Belfast have unfortunately not yet 

 been made available. The occurrence, however, of Exogyra columba in the upper 

 beds has been noted by Col. Portlock in his work on Tyrone. There seems little 

 ■doubt of the presence of the Upper Greensand in North Ireland. 



t Phil. Mag. 1850, p. 430. 



