MacMillan : shores at lake of the woods. 951 



3. Ecological embryology. — This is that department of 

 ecology which concerns itself with adaptational phenomena in 

 the development of individuals from the germ. Here the mod- 

 ern methods of experimental embryology come into play, and 

 the reactions of the developing egg to its surroundings furnish 

 the phenomena of critical interest. 



4. Ecological distribution. — This should be defined as the 

 science which treats of the reciprocal relations between phys- 

 iographic conditions and life requirements of organisms, in so 

 far as such relations manifest themselves in choice of habitats 

 and method of establishment upon them. The structural adap- 

 tations that arise when organisms accommodate themselves to 

 particular atmospheric, topographic, climatic, geological, soil 

 chemical or cosmic (including here influences of light as modi- 

 fied by latitude) conditions may properly be regarded as within 

 the domain of ecological morphology or physiology; but the 

 habitats with the resultant origin and development of plant- 

 formations present a line of scientific inquiry distinct enough 

 and worthy of special attention. The essay in hand lies quite 

 within the field of ecological distribution as thus restricted and 

 the discussion of ecological morphological details will not be 

 entered upon. 



P/njsical features of the region. 



Geographical position.— Lake of the Woods is situated be- 

 tween latitudes 49° 11' and 49° 53' N and longitudes 94° and 

 95° 35' W. It lies between the Canadian provinces of Ontario 

 and Manitoba and the state of Minnesota. From north to south 

 and from east to west it extends about sixty miles, and its total 

 area is not far from 1500 square miles. The greater portion of 

 this lies within Ontario, but parts of Muskeg bay and Buffalo 

 bay belong to Manitoba, while considerably more than one-half 

 of the Grand Traverse is within the borders of Minnesota. The 

 international boundary between Canada and the United States 

 runs diagonally across the Grand Traverse, entering the lake 

 at the mouth of Rainy river, and trending northwesterly to the 

 inlet known as Northwest Angle inlet. Here the direction of 

 the line changes abruptly and it runs due south to the 49th par- 

 allel, thence due west along this parallel. The intersection of 

 the north and south line with the 49th parallel lies in the 

 Grand Traverse, and the eccentric course of the boundary iso- 

 lates a portion of land belonging to Minnesota, known to carto- 



