OD 



cation by the Danish antiquarians of the moss deposits, 

 into (1) Boggy levels (Engmose), chiefly composed of, or at 

 least with a substratum of peat, covered with water plants 

 and grass, lying low at the bottom of valleys, and traversed by 

 water courses; these are generally less deep than the other 

 deposits, say 5 to 12 feet thick. (2) Peat hogs (Lyngmose, 

 Svampmose), large tracts composed of long-continued 

 growths of Sphagnum and Hypnum, kept wet from below 

 by concealed water supply, and usually covered more or less 

 with heather or other vegetation. The lower portions of the 

 moss consolidate into peat. They ordinarily measure from 

 8 to 15 feet in depth; and (3) Forest moss pits (Skovmose). 

 These are peculiar, and have proved the most interesting 

 of such deposits. They occur in depressions in the surface 

 of the glacial clays of the country, usually of small extent, 

 but sometimes of considerable depth, down to 80ft. or more. 

 They are distinguished by a marginal mass of tree stems, 

 with branches and leaves. These trees are always found 

 to have fallen in (towards the centre of the pit) and are often 

 so closely packed that it would seem difficult to place more 

 of them in the space. When the pit is large enough to 

 admit of it the central portion is filled up with moss, and 

 forms a small peat bog, without or with the superficial 

 growths. 



In places where time has allowed ground to consolidate 

 and still later vegetation to find footing, the Danish pits 

 arecommonly covered by successive growths of pine, then 

 beech, then alder, and lastly hazel. 



M. Steenstrup has calculated that to complete the develop- 

 ment of such a deposit, of say 10 to 20 feet in thickness of 

 peat, some 4,000 years may be required; but the period is 

 at present conjectural only. 



In the course of elaborate researches it has been ascer- 

 tained that the Danish forest pits exhibit an earliest age of 

 forests of pines (P. abies^, a tree which is, except so far as 



