4IO 



Minnesota Plant Life. 



flowers are purple, while in others they are yellow. The shapes 

 of the leaves and of the flower heads differ in the different kinds ; 

 and the arrangement of the flower heads varies slightly, though 

 ordinarily they are either solitary or in flat-topped clusters. 

 To this genus of plants belongs the artichoke, the rootstock of 

 which bears tubers. 



The tickseeds are little yellow-flowered composites, with the 

 pappus much reduced, appearing commonly as a couple of small 



Fic,. :iur). Aslcrs and goUk-n-iod. I5anks of the Mississippi. After pliotograpli l.y Williams. 



teeth at the end of the somewhat winged nutlet. The bur- 

 marigolds produce yellow flower heads, from the disk flowers 

 of w^hich arise fruits with two or more strongly barbed bristles 

 upon each, for in these plants the ])appus has lost its aeronautic 

 characters and is adapted to fasten the fruits to the bodies of 

 wandering animals. The little flattened, pitchfork-like seeds 

 which stick to one's clothes in the autumn arc llioso of the biu'- 

 marigold or beggar-licks. The several different varieties are 

 known bv the shape of the nutlets, by the foliage and by the 



