fall from the perpendicular, and the ridge bristles with these 

 oblique projecting plates presenting "a savage and chaotic deso- 

 lation that is probably without parallel in eastern North 

 America." 



The very diverse conditions of surface upon the other sum- 

 mits are due largely to simple differences in firmness of the 

 constituent rock. "Thus, parts made up of the more friable red 

 granite (not dividing into plates) are covered with small sized 

 fragments, rounded by decay. These assume, over wide stretches, 

 the size and almost the arrangement of cobble paving stones and 

 in a few places the aspect of gravelled areas." Such conditions 

 prevail particularly upon the slopes of the northern summits. 



"Again, the middle of the northward slope, between the Table- 

 land and the Saddle, is piled with blocks of the firmer red gran- 

 ite, riven from the mass beneath, of size so great as to render 

 travel over them extremely difficult. The tableland is in parts 

 smoothed by a covering of wholly disintegrated material, but 

 in general is strewn with tabular blocks that increase upwards 

 toward West Peak in size and number." 



"The slopes south from the two chief peaks are covered with 

 loose, angular, often tabular fragments, as far down as the 

 (so called) tree-line, which is everywhere very low, leaving an 

 unusual amount of naked rock above." "The whole rock sur- 

 face of the mountain has been so shattered by frost action that 

 only on faces of cliffs too steep to admit of an accumulation of 

 detritus is rock to be found in situ." 



The structure then of the red granite, which makes up the 

 upper 700 feet of the mountain, has determined a variety of 

 savage conditions from a blade-like crest to long slopes covered 

 with huge angular or tabular blocks or fields of cobble stones. 

 These conditions are all very significant in their bearing upon 

 timber lines and the genetic development of plant societies upon 

 the higher slopes. 



IV. THE ORIGIN OF THE MT. KTAADN FLORA. 



In studying the flora of North America the identity of plants 



on isolated mountain summits and regions far to the north is a 



noticeable fact. The floras of Mt. Washington, Ktaadn, Labra 



dor, and east Arctic America, localities widely separated by miles 



II 



