169 



Brigcron ramosits (Walt.) BSP. Hanover and Oquawka areas, 

 in the bunch-grass and Panicum psetidopubcsccns associations; Win- 

 nebago area, in the black oak forest. 



Brigcron canadensis L. An interstitial in the bunch-grass in the 

 Hanover area, and on blowout deposits in the Ocjuawka area. 



Antcnnaria plantaginifolia (L.) Richards. Hanover area, in the 

 mixed forest association. 



Antcnnaria sp. One or more unidentified species of Antcnnaria 

 are common in the bunch-grass and black oak forests of the Hanover, 

 Winnebago, Amboy, Dixon, Oquawka, and Havana areas. 



Gnaphalinm polyccphaluni Michx. Hanover area, in the bunch- 

 grass ; Amboy and Oquawka areas, in the black oak forest ; in the 

 latter area also in the Stcnophyllus and blowout thicket associations. 



Silphinni laciniatum L. Along roadsides in the Amboy area. 



Silphiuni intcgrifolinui Michx. Amboy area, in the black oak 

 forest. 



Parthcniiini intcgrifoUnni L. Hanover area, in the mixed forest 

 association; Amboy area, along sandy roadsides. 



Ambrosia ortcniisiifoHa L. A weed in the waste grounds in the 

 Oquawka and Winnebago areas. 



Ambrosia psilostachya DC. Observed in the Hanover, Winne- 

 bago, Dixon, Oquawka, and Havana areas, and probably in the oth- 

 ers as well ; a common interstitial in the bunch-grass, black oak, and 

 Panicum pscudopubcsccns associations, and abundant in the blow- 

 sand association. 



Xanthium commune Britton. A weed in sandy fields in the 

 Oquawka area. 



Rudbcckia hirta L. Hanover, Winnebago, Havana, and Oquawka 

 areas, abundant in the black oak forest, and occasional in the mixed 

 forest and bunch-grass. 



Brauncria pallida (Nutt.) Britton. Hanover, Dixon, and 

 Oquawka areas, in the bunch-grass association ; Amboy area, along 

 roadsides. 



Lcpachys pinnata (Vent.) T. & G. Winnebago area, in a clear- 

 ing in the black oak forest. 



Hclianthus Icnticularis Dougl. Oquawka area, in the blowsand 

 association. 



Hclianthus scaberrimus Ell. Hanover and Oquawka areas, com- 

 mon in the bunch-grass and Panicum pscudopubcsccns associations; 

 Amboy area, along sand roadsides. 



Hclianthus occidcntalis Riddell. Common in all seven areas in 

 the bunch-srrass and black oak associations. 



