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I have next to call your attention to an able sketch of the geo- 

 logy of Denmark, which you will find at some length in our Pro- 

 ceedings, from the pen of an eminent Danish naturalist, Dr. Beck, 

 of Copenhagen. He describes in Bornholm, besides the granitic and 

 Silurian rocks, certain strata which appear to agree with our Weal- 

 den group in mineral character and fossil plants, some of these 

 being the same as those found in the Hastings sands, although the 

 shells are marine. In Bornholm this formation is characterized by 

 containing coal. The most remarkable feature in the geology of 

 Denmark Proper is the great development of the cretaceous system 

 above the white chalk with nodular flints. In the island of See- 

 land the ordinary white chalk is covered with a hard yellowish 

 limestone containing some fossils of the white chalk and others 

 peculiar to itself, especially univalves of the genera Trochus, Fusus, 

 Voluta, Oliva, Cyprsea, and Nautilus. At Faxoe this rock consists 

 of an aggregate of corals of unknown depth, but certainly more 

 than forty feet thick. When I myself visited the Faxoe quarries in 

 ] 834 in company with Dr. Forchhammer, the rock struck me as 

 agreeing with the description usually given of the limestone in re- 

 cent coral reefs. The fossil zoophytes of Faxoe are often cemented 

 together by white chalk, which may recall to your recollection the 

 recent chalk which Lieut. Nelson has presented to our museum 

 from the coral reefs of the Bermudas. This recent substance is 

 not distinguishable from some of the white marking chalk of En- 

 gland, and like it is composed of pure carbonate of lime. It is in 

 fact a white earthy mud, known to be derived from the decomposi- 

 tion of the softer corallines, such as Eschara, Flustra, and Celle- 

 pora. These observations support an opinion which has long been 

 entertained by some geologists that all chalk may be derived from 

 the decomposition of shells and zoophytes. 



While on this subject I may mention a discovery made by Mr. 

 Lonsdale during the last summer, and which he has permitted me 

 to announce. In arranging our collection he has found that our 

 common white chalk, especially the upper portion of it, taken from 

 different parts of England, (Portsmouth and Brighton among others,) 

 is full of minute corals, foraminifera, and valves of a small ento- 

 mostracous animal resembling the Cytherina of Lamarck. From 

 a pound of chalk he has procured, in some cases, at least a thou- 

 sand of these fossil bodies. They appear to the eye like white 

 grains of chalk, but when examined by the lens are seen to be fossils 

 in a beautiful state of preservation. 



According to Dr. Beck there is a whitish and hard chalk above 

 the Faxoe beds almost entirely made up of pulverized zoophytes 

 including bivalves and Echini, chiefly of the same species as those of 

 the white chalk with flints, and with corals like those of Faxoe. 

 There are layers of flint or chert in this upper division. These 

 conclusions, drawn from a careful examination of an extensive series 

 of the Danish fossils, are very important, for it was formerly ima- 

 gined by Dr. Forchhammer that the Faxoe beds and the overlying 

 chalk belonged to the calcaire grossier, an idea suggested by the 



