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DlATOMACEOUS DEPOSITS FROM JUTLAND. 



By F. Kitton.* 



The remarkable deposits found in and near the island of Mors 

 have lately attracted the attention of microscopists (principally 

 through the introduction of the beautiful slides of Herr Muller, of 

 Wedel, the preparer of the Typen Platte). This deposit, with 

 perhaps one exception — the so-called " Bermuda Earth ' (New 

 Nottingham deposit) — is richer in bizarre and beautiful cliatomaceous 

 forms than any other hitherto discovered. The material best 

 known in this country is that called " Cemenstein," from the island 

 of Mors, a large island situated in the Liimfjord (lat. 56° 50' N., 

 long. 8° 40' W.). This fjord, the most extensive in Jutland, runs 

 from east to west, connecting the North Sea with the Kattegat. 

 The Cementstein from Mors resembles a dark grey slate, inter- 

 spersed with white veins. The silicious organisms of which it is 

 chiefly composed are held together by a calcareous cement, and 

 when submitted to the action of acids are slowly disintegrated with 

 effervescence. A similar deposit occurs in Fuur ; it is, however, 

 more difficult to separate, and but slightly affected by acid, and 

 resembles the deposit known as " brown coal." A third deposit is 

 found in Nykjobing, a small town or village on the western side of 

 Mors Island. This deposit is of a greyish white colour, still more 

 difficult to reduce than the preceding, strong acids not affecting it 

 in any appreciable degree, and only by the assistance of caustic 

 potash or soda can the organisms of which it is composed be 

 effectually separated-. One of these deposits seems to have been 

 known to Professor Quekett, as he figures a small Triceratium in 

 his " Histology " (vol. ii., p. 74, fig. F), and which is apparently a 

 small form of Trinacria excavata, similar to the variety found in the 

 Nykjobing deposit ; this, the Professor says, is from "Jutland slate." 

 Dr. Heiberg, in his " Kritisk oversigt over de Danske Diato- 

 meer," describes a few of these deposit-forms, and also gives some 

 excellent figures of them. 



* Communicated by M. C. Cooke, M.A., June 24th, 1870. 



