*26 The Botanical Gazette. [May, 



end of the bog comes in contact with the 'high land, and that 

 it is for some distance parallel with it, that it is long and 

 relatively narrow, and that on the side away from the higher 

 land it sinks down to a large bog of the flat kind. I think it 

 extremely probable that a huge cold spring (or a line of them) 

 comes out from the high land at the upper end of the bog, 

 and the water then flows along toward its lower end on the 

 bottom, being soaked up as it goes. The bog then grows and 



carries up the water sponge-like with it, and when off to one 

 side the influence of the spring diminishes and is finally lost, 

 the ordinary bog conditions begin to prevail. All this is con- 

 firmed by the fact of which Mr. Boardman assures me, that 

 there flows out from its lower end a brook of clear, cool water, 

 large enough so that in times past it has turned the wheel of 

 a mill. Water of this character does not flow from common 

 bogs and a spring origin seems necessary to account for it. 



One other point remains to be explained. Why are they 

 treeless and shrubless? This I believe to be due to the cold- 

 ness of the water supplied by the springs. The temperature 

 is too low for the growth of the roots of shrubs or trees. Its 

 coldness has been already referred to; even at a depth of but 

 a few inches this was very marked. It is perhaps, too, a point 

 x of importance that the bog bears in greatest profusion the 

 cloud-berry, Rubits C kamasnwrus ; so abundant is it that the 

 inhabitants resort to the bog with pails and gather it in great 

 quantities. This northern plant finds so congenial a home 

 but rarely in these latitudes, and seems to point to the cold 

 conditions prevailing in the bog. I advance this explanation 

 but tentatively. Perhaps some of our botanists who take 

 their outing m that favored region will give it their attention. 



Harvard University, Cambridge, Mass. 



Notes on the flora of the St. Croix region. 



E. J. HILL. 

 (Concluded from p. iij.J 



The rest of the time in the St fmiV -„~- • *„ tr> 



; ,c •" me ^r. ^roix region was given to 



the Chesago Lakes, situated a few miles west of Taylo?s Falls. 

 Three days of the early part of September were mainly de- 

 voted to an examination of the water-plants, or to those of 



