1869.] JIATTIIEW — ON PLANTS IN ACADIA. 161 



transported in the course of time, upon floe ice and drift-wood, 

 to the north-eastern pat ts of America. 



Accordingly we find little difficulty in tracing back the course 

 of the Boreal and Arctic types north-westward across the 

 Continent of America, toward Asia. Attached to the table of 

 Boreal forms are three columns shewing the range of the species 

 to the N.W., compiled from the late Sir W. J. Hooker's Flora 

 Boreali Americana, Dr, Gray's Flora of the Northern United 

 States (1859), and a list of the plants collected at Anticosti by 

 Prof. A. E Verrill. Labrador and Newfoundland are bleak, 

 inhospitable countries, whose flora is but imperfectly known ; yet 

 of the three score species of this list, more than one-half have 

 been gathered there. In the St. Lawrence Valley, chiefly in that 

 part of it below the great Lakes and around Lakes Huron and 

 Superior, more than two-thirds of the list of Boreal species 

 occur; — many of these being only known in the far western 

 parts of the Valley about Lakes Superior and Huron, or on the 

 mountain tops of New England and New York. The presence 

 of these species in Acadia is easily accounted for when it is 

 considered that there is a continuous water communication from 

 the great lakes of the interior to the northern confines of Acadia. 

 But it is more remarkable, if we fail to give due weight to the 

 transporting powers of the Polar Current, that all the high 

 Northern forms, with half a dozen exceptions, should be already 

 known as indigenous to the North West Territory, between Red 

 River, the Arctic Sea, and the Rocky Mountains. Moreover, 

 there are three species which, if one may judge from the authori- 

 ties above quoted, are not known to occur in the interspace 

 between this region and Acadia, or to the N.E. of the latter. 

 These are Collomia linearis, discovered by Mr. Fowler on the 

 Gulf coast; Vil/a cuspidata, found by Mr. Goodale on the 

 Upper St. John, and Oxytropis campcstris, gathered by Prof. 

 Baily on the Main St. John, This list of adventurous emigrants 

 from the N.W. would be largely increased were we to include 

 species which occur in the intervening country only on the 

 mountain tops of New England and New York. 



The River St. John appears also to have played an important 

 part in distributing plants throughout Acadia, and a few remarks 

 on its peculiarites may, therefore, not be out of place. This is 

 one of the most considerable of the numerous rivers which take 

 their rise in the Appalachian range, and about one-half of 



