Diphasium Diphasium, (Pursh) Rothm.

2. D. tristachyum (Pursh) Rothm. View in CoL , Feddes Repert. 54: 65 (1944)

( Lycopodium chamaecyparissus A. Braun ).

Stems deeply subterranean; erect shoots repeatedly branched and caespitose; finer branches, 1-2-1 -5(-2) mm wide, somewhat flattened. Lateral leaves as wide as dorsal; ventral leaves on the finer sterile branches 1-1-5 mm long, i to | as wide as the branches. Spikes pedunculate; sporophylls broadly ovate, acuminate; spores 30/* in diameter. 2/z = 46. C. Europe, extending to S. Fennoscandia, N. and C. Russia, Romania, C. Italy and the Pyrenees. Au Be Cz D a G a Ge Fe He Ho Hu It Ju No Po Rm Rs (B, C) Su.

Hybridization between 1 and 2 seems to have occurred in some places, and in S. Finland hybrid derivatives are commoner than D. tristachyum , which is very rare. It is also doubtful whether the European and N. American plants, which are here both referred to D. tristachyum , are rightly placed in the same species.