201 



Glacial or Turbarian stage, represented by mountain glaciers, and 

 arctic valley floras, at least towards its close. These consist largely 

 of the herbaceous arctic willows such as Salix reticulata and her- 

 bacea with Dryas octopetalata, etc. The fifth interglacial is marked 

 by a gradual amelioration of temperature, the arctic willows 

 being replaced by a close growth of Salix arbusciila with Poten- 

 tilla comarwn, Empetrinn nigritvi, Arctostapliylos alpina, and other 

 sub-arctic forms until finally the moor is converted into a forest 

 with Betiila alba or Pimis sylvestris predominating, the latter with 

 an undergrowth of Calltina. These conditions are followed by 

 increasing humidity and precipitation until wet moorland {Sphag- 

 mmi) has replaced the forest and the climate becomes consider- 

 ably cooler with slight alpine glaciation. Soon, however, the 

 climate becomes warmer, more genial, and drier in fact than it is 

 at the present time, and another forest of Pimis sylvestris of large 

 size and with an undergrowth of Calluna and some Corybis and 

 Alniis occupies the region, f Succeeding the pine forests is 

 another era of wet moorlands {Sphagman, Scirpiis) which gradu- 

 ally changed to the present somewhat drier condition. 



While it is regrettable that all of the plant forms discovered 

 have not been identified and listed and while the manner of pres- 

 entation is susceptible of improvement, the study as a whole is an 

 extremely valuable one and shows the possibilities in a line of 

 work almost wholly neglected in America. It is to be hoped that 

 it will furnish a stimulus to botanists favorably situated in our 

 own northern states and induce them to get a little way below 

 the surface in their ecological studies. 



Edward W. Berry, 



Johns Hopkins University. 



AN EDITORIAL PLEA 



A contemporary magazine writes as follows : We cannot 

 expect the " man who pays " to continue to pay unless he re- 

 ceives value for his money, but the value of a scientific journal, 

 unlike that of a popular magazine, is dependent entirely on gra- 



f Proximity to the Atlantic caused the wet moorland to persist in western Scotland 

 at this time. 



