^ fruit winged; calyx small but evident, disk prominent; stylopo- 

 dium(in herbarium specimens) sunken; pedicel of central flower 

 not much shortened if at all. 



Thaspium aureum(trifoliatum) . 



M fruit ribbed(not winged); calyx small, usually inconspicuous; 

 disk small; stylopodium flattened; central flower(and fruit) 

 sessile or sometimes short pediceled, 

 Zizia. 



