THE TALL MIDSUMMER WEEDS. 205 



leaves are somewhat angularly shaped ; the lower 

 ones are variously three- to seven -lobed, with mar- 

 gined stems ; the upper ones are 

 oblong, lance - shaped, mostly 

 undivided, and they almost 

 clasp the main stem. This 

 plant will also be found in 

 the tangled brush of the clear- 

 ing, where its inconspicuous 

 flowers are scarcely relieved against 

 a confused and green background; 

 it blooms in late August. 



The tall rattlesnake root (Pre- . 

 nanthes altissima) is an imposing 

 species common in the rich wood- 

 lands of the ^orth, which some- 

 times attains a height of seven 

 feet. It bears a long narrow pani- 

 cle of inconspicuous green and dull- 

 white flowers, which top off the 



Prenanthes serpentaria. 



slender weed with a slightly curved, 

 loose, leafy cluster, and also spring from the junction 

 of the leaves with the main stem. The leaves are 

 variously shaped, but all have distinct stems ; they 

 are triangular, ovate, toothed or cleft, and frequently 

 three-to five-parted. Still another species, P. alba, 

 sometimes called common white lettuce, is also quite 



