KEY To THE LYCOPODIUMS. 



I. Sporangia in the axils of ordinary leaves 



Leaves flat. Lowland species . . L. luctduhiui 



Leaves curved upward. Mountain species Z. sclago 

 II. Sporangia in cone-like spikes 



Sterile stems prostrate ; fertile, erect, unbranched 



Prostrate stems usually branched L. alopecuroides 

 Prostrate stems short, seldom branched 



Rooting throughout . L. Carolinianum 



Rooting at base and tip only . Z. inundatum 

 Fertile and sterile stems erect ; rootstock creeping 

 Cones closely sessile 



Averaging an inch or more long Z. obscurum 

 Averaging less than an inch long 



Z. annotinuin 

 Averaging less than half an inch long 



Z. cernuum 

 Cones apparently stalked 



Branches about four-sided . Z. alpinum 



Branches round 



Leaves bristle-tipped, i inch long 



Z. claixitum 

 Leaves not bristle-tipped, shorter 



Z. Sttchense 

 Branches flattened 



Cones two to four, peduncle long, stout 



Z. compIanatiiDi 



Cones one to three, peduncle short, slender 

 Z. sabinafolium 



