Minnesota Plant Life. 



411 



flowering heads. One, the highest type of aquatic vegetation 

 in Minnesota, is called the water-marigold, or Beck's marigold, 

 and is found in ponds and brooks. Its submerged leaves are 

 all dissected into thread-like lobes. The flowering heads, dis- 

 tinctly composite in their appearance, are thrust out of the 

 water, and just below them a few willow-shaped leaves are borne. 

 The nutlets produce from three to six barbed bristles and are 

 fitted for attachment to the plumage of birds or the fur of 

 animals. 



The yarrow is an erect herb, a foot or two in height, with 

 leaves of strong, tansy- 

 like odor, dissected pin- 

 nately into numerous tiny 

 segments. The heads are 

 very numerous, borne in 

 dense terminal flat-topped 

 clusters. The ray flow- 

 ers are white or pink. 

 Tansy, a common herb 

 escaped from cultivation, 

 is known by the highly 

 aromatic foliage and the 

 pinnately divided leaves. 

 Wormwoods, of which 

 there are several sorts, 

 contain the peculiar bitter 

 principle used as a flavor- 

 ing substance in the man- 

 ufacture of absinthe. 

 Many of them are very 



white or silvery, from the numerous hoary hairs with which the 

 leaves and stems are covered. The heads are small and aggre- 

 gated in dense spikes, compound racemes or panicles, and the 

 foliage exhales a characteristic aromatic odor. Colts'foots, to 

 be found in marshes, may be known by their thick horizontal 

 rootstocks, by their scaly stems on which, in flat-topped clus- 

 ters, a few heads are borne, and by their large root-leaves — in 

 one variety palmately divided like the leaves of some anemones, 

 and in another of a broadly arrow-head shape. Related to the 



Fig. 206. Rosinweed compass-plant. After Britton 

 and Brown. 



