264 OHIO STATE ACADEMY OF SCIENCE. 



Branches pendent, leaves small, very fine net veined, 

 primaries and secondaries irregular; capsules short 

 globose conic, remaining green in fruit, staminate 

 plants practically unknown. S. babylonica. 



Shrub, often growing in dense clumps with many slender 

 stems; leaves often very long, linear-oblong, with a 

 strong marginal vein and distant primaries, smaller 

 veins except a few costals vanishing; catkins often 

 in cymose clusters which continue flowering all sum- 

 mer, or the earliest only leafy bracted. 5. interior. 



Leaves short and broad (more than 1 cm.) inclined to 

 be very wooly ; cymose clusters of catkins very pro- 

 nounced, carpellate plant rare. 5. interior wheeleri. 



Filaments glabrous, catkins coming before or with the 

 leaves but not on leafy branches unless in fruit. 



Capsules pubescent at least in flower. 



Styles short and inconspicuous, less than half as long 

 as ovulary. 



Leaves mostly broad, coarsely serrate or entire; cap- 

 sules long conic, very hairy ; upright, many 

 stemmed shrubs preferring lowland swamps. 



Capreae. 



Catkins at anthesis seldom 2 cm. long, not very 

 wooly, bracts conspicuous, scales light brown, 

 persistent, pedicel very long, filaments slender; 

 venation prominent below, leaves dirty white 

 tomentose, especially on the veins. 5. bebbiana. 



Catkins seldom less than 2 cm. long, wooly pussies, 

 bracts small, scales almost black, filaments 

 thick, pedicel medium; leaves mostly glab res- 

 cent, veins not very prominent below. 



5. discolor. 

 Leaves narrow. 



Leaves undulate-revolute to entire, primaries prom- 

 inent on the under surface, distant, coming 

 out at right angles and arching or looping 

 regularly to the base of the leaf ; aments small 

 short pussies without leafy bracts, capsules 

 long conic, very hairy; upland swamps and 

 hillsides. 5. humilis. 



As above but smaller throughout; leaves up to 

 5 cm. long, aments less than 1 cm. long, 

 shrub less than 1 m. tall; prairies especially. 



5. humilis tristis. 



