MacMillan : shores at lake of the woods. 981 



opposite direction. When the back strand is not cut off from 

 the general back country population by ditches and marshes, 

 there is a marked development of back country types of plants 

 along ridges in the back strand so that just as mid-strand bars 

 are inserted into the back strand from the lakeward side these 

 masses of back country plants are thrust in from the landward 

 side. Hence, a back strand bordered landward by coniferous 

 formations will itself partake of the coniferous character while 

 one bordered by dicotyledonous trees will have rather the 

 deciduous plants as its characteristic inhabitants. Yet even to 

 this apparently universal generalization there are notable ex- 

 ceptions as when a Quercus or Populus formation maintains 

 itself oil the back strand without admixture of Pinus divaricata 

 although the general back country formation is consistently 

 Pinus, Picea and Abies forest. 



Upon larger islands and upon the main land this back- 

 country influence is especially strong. Upon smaller islands 

 — omitting naturally those which are too small for the full 

 development of strand zones — there is less to be made out. in 

 its study. A constant and vigorous struggle for supremacy is 

 maintained by the various plants of the general population and 

 many of these will light their way down to the back strand, 

 accepting there unusual and unfavorable conditions. Upon the 

 back strand, then, it is common to find stray plants maintaining 

 themselves feebly upon the dark sand and evidently wanderers 

 from the region behind. Thus upon the Oak point back strand 

 one finds small, dwarfed trees of Pinus sirobus and Pinus 

 resinosa and even of the swamp-loving Picea mariana, estab- 

 lished upon the sand. With these come Arciosiapltylos and 

 Comandra. It follows, too, as a matter of course that back 

 strand, limiting a region of monotonous plant population, will 

 itself receive influences less complex than where it faces a 

 region of diversified population. 



Since the influence of aquatic birds was grouped among con- 

 ditions arising lakeward, it would be appropriate to consider 

 under this topic the inlluence of land animals. At Lake of the 

 Woods this can hardly be a very important biological influ- 

 ence, but the advent of bears, deer, moose or caribou and 

 especially their habitual visit to certain pools of the back 

 strand must have its influence upon the vegetation. Thus at 

 one pool on the Oak point back strand, frequented, I was told, 

 by deer, stray plants of Ledum, Eriophorum and Beckmannia 

 were noted, probably brought in by the roving animals from 

 some distant swamp. 



