14 
Stem prostrate, slender. Leaves lanceolate, acute, ciliate. Fer- 
tile leaves forming a cylindrical spike in the top of ascending 
branches, larger than the sterile leaves, spinulose ciliated. Spo- 
rangia containing powdery microspores or few larger (about 0,6 mm.) 
macrospores. 
Am.: West Greenl. 60° 53’—64° 8’ (!). 
Geogr. area: Northern North America, Iceland, Fzerées, British 
Islands, France, Pyrenees, Scandinavia, Denmark, Central European Moun- 
tains, Northern Russia, Caucasus, Siberia. 
28. S. rupestris (L.) Spring. 
F. Kurtz, Fl. d: Tschuktschenh p. 482: Trautv. Fl. Kolym. p. 574. 
Stem prostrate much branched, forming close tufts. Leaves 
crowded, linear lanceolate, appressed imbricated, minutely ciliated, 

Fig. 10. Selaginella rupestris (L.) Spring. ; 2/3 nat. size. (Spec. from Vancouver Island). 
tipped with a bristle. Fertile leaves in 4 ranks on ascending 
branches. Spores as in the preceeding. 
As.: Mouth of the Kolyma, Chukches Land (!). 
Geogr. area: North and South America, Central Africa, Southern 
and East Asia. 
Order VI. ISOETACEAE Trevisan. (By C. H. OsTENFELD). 
The order consists only of the genus: 
1. ASOETES..ik: 
29. |. lacustre L. 
Fl. D. t. 2742. 
Plants growing on the bottom of lakes. Stem short and tube- 
rous with many subulate, dark green, short pointed leaves, which 
at the base bear sporangia, either containing brownish microspores 
