300 Flonstik, Geographie, Systematik etc. 



nity Ol" the Sphagnum-moors, 7. The heath Vegetation, 8. The forest 

 Vegetation, and 9. The culture formations. 



Chapter IV is the main part of the paper; it is a list of all the 

 wild growing and naturalised species ol~ fiowering plants and pteri- 

 dophj^tes with all the finding places. 1212 species are enumerated. 



C. H. Ostenfeld. 



Davis, C. A., Salt Marsh formation near Boston and its Geo- 

 logical Significance. (Economic. Geology. V. p. 623 — 639. 1910.) 

 Salt marshes near Boston are described and their actual struc- 

 ture as determined b}^ over 100 test sections is shown to be opposed 

 to the prevalent view of their genesis i. e. by silting up of bays, 

 estuaries, etc., followed by a growth of eel-grass overlain, as shal- 

 lowing progressed, by remains of salt water grasses and sedges, in 

 constantly increasing numbers with increasing elevation. The niajority 

 of sections do not bear out this hypothesis, many showing unmis- 

 takable evidence of fresh water origin in the character of, and 

 plant remains contained in, the peat. The latter comprises conside- 

 rable wood}^ materiai including large pine stumps. Where the peat 

 showed salt marsh materiai the contained plants were not eel-grass 

 or other forms which withstand submergence or grow at half tide 

 but on the contrary were plants which grow today at or near high 

 tide, the peat showing the same structure and origin throughovUlevel. 

 The existing marsh flora of this region is divided into the 

 following zones: 



1 The salt-thatch zone which covers tidal banks extending down 

 to abaut half tide mark and except for occasional stragglers consists 

 of Spartina glabra var alternißora. The remains of this plant are 

 entirely characteristic and easil}^ recognizable in the peat. 



2 The next zone forming the general surface of the marsh and 

 submerged an inch or two for from one to four hours ever}" day 

 consists for the most part of Spartina patens and Distichiis spicata, 

 and their remains also are readily recognizable in the peat. The 

 other and higher zones are not characterized in the present paper. 



The authors obvious conclusions are that the facts can have 

 but one explanation — either the sea level has increased progres- 

 sively or the land has subsided and furthermore the deposits show 

 indisputably the amount of subsidence since the starting plane is 

 known within narrow limits. They show moreover the rate at which 

 this subsidence has occurred since if this sinking was faster or 

 slower than the upbuilding of the turf, Spariina glabra or marine 

 types would replace Spartiiia patens in the first case, or plant types 

 characteristic of drier zones would replace it in the second case. 

 Oscillation of the coastal margin would also be recorded with equal 

 fidelity. The deepest deposit of peat was found at Nahant where 12 

 feet ot salt marsh turf was found overl3äng 2 feet of fresh water 

 peat resting on a sandj?" substratum, indicating that the land was 

 at least 16 feet higher when the fresh marsh existed than it is at 

 the present time. 



Finally the bearing of these marsh peat phenomena upon some 

 of the geological problems connected with the formation of coal 

 are briefly discussed. Berry. 



Ostenfeld, C. H., Galittm molhigo L., var. tyi'olense (WWd.) Brig. 

 (Bot. Tid.sskr. XXX. 3. p. 469. Kjöbenhavn 1910.) 



Of late years a form of Galiiim has been found in Dan mark 



