THE GENERAL CHARACTERS OP SEEDS 477 



COMPOSITAE, COMPOSITE FAMILY. 



/ 

 Baldwin's Iron weed {Vernonia baldwini Torr.). 



Achenes practically indistinguishable from those of the follow- 

 ing species. 



Pieure 347A Figure 347B 



Fig. 347. Ironweed' seeds. A. Vernonia fasciculata. B. Ternonia baldwini. 

 , ■ . Achenes with pappus. 

 (Drawings Charlotte M. King.) 



Ironweed {Vernoma fasciculata Mx.). 



. Achenes 3-3.-5 mm. long, land 1 mm. broad; general form slender, 

 cylindrical, often slightly curved; strongly 9-10-ribbed, ribs of 

 same color as achene, pale brown; tuft of purplish brown pappus 

 bristles attached at larger end ; length of pappus hairs 6 mm. 



"White Snakeroot {Eupatonumurticaefolium Reichard). 



Achene long, 5-angled, prominently grooved between the angles 

 oue-twelfth to one-tenth inch; generally blackish except at the 

 base where it is yellowish ; the scar at base with a small circular 

 opening, and whitish border; smoothish (see figure), pappus of fine 

 white capillary bristles; the upper part of beak expanded into 

 candelabra form> bearing the ."^omewhat fragile pappus. 



Joe-Pye Weed (Eupatorium purpureum L.). 



Achenes smooth, prominently ribbed; 5-angled, truncate; about 

 one -eighth of an inch; long; base white; pappus with numerous 

 tawijy-colored, capillary bristles. Miss Mary Nichols, who studied 

 the achenial hairs of E. villosum, finds that they are short with 

 lateral canals. The achenial hairs of- E. purpureum, according 

 to Mr'. Fracker, are simple, in E. villosum duplex. 



