1910] The Ottawa Naturalist. 51 



Shepherdia canadensis is also very abundant in spots. Many 

 herbaceous plants, a^few^not^seen]_elsewliere, find a congenial 

 home here. On the shaded sides of high dunes are Oryzopsis 

 racemosa and Carcx eburnea and on the drifting shore and dunes, 

 bugseed in abundance. In spots Buchnera americana, Aster 

 ptarmicoides and Viola arenaria are frequent. In a few places 

 on the Delta Islands, xerophytic conditions prevail. Within a 

 small area on Squirrel Island the following association of plants 

 was observed: Liatris scariosa, Hieraciuni longipiluni, butterfly- 

 weed, wild lupine, Lespedeza capitata, Ceanothus americanus, 

 Gentiana linearis, Bucknera americana and Andropogon scoparius. 

 f*^ Without particular reference to habitat and divisions given 

 above, some localities are noted for the appearance of one or 

 more species seldom seen or not noticed elsewhere. At the north 

 end of Walpole Island the scarlet painted cup and Cerastium 

 arvense oblongifolium are abundant, the latter not noticed else- 

 where. About the middle of the north half of the same island, 

 several spots are thickly covered with Silphium terebinthinaceum, 

 long ago reported by Prof. John Macoun, this, very probably, 

 being its northern limit for our locality. On the bank of the 

 Aux Sables River Mr. Newton Tripp, of Forest, found Cacalia 

 tuber osa and Astragalus neglectus, both rare for this region. In 

 and about a large pond north of Sarnia, Utricularia resupinata 

 is abundant. 



It is perhaps not best to go into the well known methods of 

 plant distribution by means of seeds, and the various ways in 

 which they are brought from one country to another, yet it is 

 interesting to notice the great changes taking place in a com- 

 paratively new country. At Point Edward, where the Grand 

 Trunk Railway formerly crossed into Michigan, the following 

 introduced plants have been well established for a number of 

 years in the streets and waste places: Datura stramonium, 

 D. iatula, Ambrosia psilostachya, Amaranthus blitoides, Russian 

 thistle, catnip, Solanum carolinense. Euphorbia lucida, Artemisia 

 vulgaris, A. pontica L., Echium vulgare, Ribes aureum-, matrimony 

 vine, Linaria vulgaris, L. minor, Verbena strict a, V. bracteosa, 

 Cycloloma atriplicifoliufn, Chenopodium botrys, Erysimum parvi- 

 florum, Thlaspi arvense, Bromus brizaeformis , B. tectorum. 

 Sisymbrium altissimum, Petalostemun purpureum and others. 



It is very natural for an observer in looking backw^ard to 

 contrast conditions existing before the advent of Europeans 

 with those of the present time. The great change that has 

 been going on from time to time in various parts of North 

 America for 200 years and more, from a state of nature to one 

 of civilization has occurred here in recent years. From an almost 

 impassable forest, the country has been changed by the activity 



