192 MINNESOTA BOTANICAL STUDIES. 



Grindelia squarrosa (Pursh) Dunal. 



This is another western plant that seems to be travehng east. 

 It has but recently become well established in the railroad yards 

 at Montevideo. 



Lactuca scariola L. 



Another Old World weed that has but recently arrived at 

 Montevideo is this species. It is spreading with great rapidity. 



Senecio vulgaris L. 



Recently arrived at Montevideo, this plant is becoming com- 

 mon as a weed in gardens and waste grounds. 



Poa pseudopratensis Scrib. & Ryd. 



A Poa collected at Clara City, in Chippewa County, has been 

 identified by Professor Lamson-Scribner as this species. 



Fraxinus lanceolata Borck. 



A study of this species based on a large collection of ma- 

 terial from the prairie portion of the State, some of which was 

 sent east for comparison, makes it probable that all of our ash 

 trees are referable to this species. F. Americana appears to be 

 absent from western Minnesota. 



Cactus viviparus Nutt. 



This cactus is found quite abundantly on granite ledges in the 

 ancient valley of the "Warren," about two miles southeast of 

 Ortonville. Its bright red flowers are strikingly beautiful. 



Astragalus flexuosus (Hook.) Doug. 



This species is quite plentiful near the railroad yards at Or- 

 tonville. 



