Family EQUISETACEA 13 
Phylum I]. CALAMOPHYTA. 
[Class EQUISETINEAE. 
EQUISETALES. 
1. EQUISETACE. 
1. Equisetum. 21. 
Horse-tails, Scouring-rushes, Joint-weeds. 
Stems of two kinds, the fertile not green, shedding spores in early 
spring; the sterile appearing later, green and much _ branched. 
1. E. arvense. 
Stems all alike, spores shed in summer or fall. 
Stem with many furrows, usually more than ten. 
Hollow of stem % of stem-diameter or more. 
Stomata scattered, stems at length branched. 2. E. fluviatile. 
Stomata in rows, stems simple’or nearly so. 4. E. levigatum. 
Hollow of stem less than % of stem-diameter; stems large, 
ridges tubercled. 3. E. robustum. 
Stem 5-10-furrowed, slender; central cavity small or wanting. 
5. E. variegatum. 
1. Equisetum arvense L. Common Horse-tail. 
Common throughout the state, often in sandy soil, wet meadows and 
banks. Ashland; Anselmo; Brownville; Lincoln; Milford; Natick; 
Nebraska City; Long Pine; Pine Ridge; Thedford; Weeping Water; 
Wymore; Sioux canyon; Hat Creek basin. 
2. Equisetum fluviatile L. Swamp Horse-tail. 
Swampy places by streams or ponds. Burwell; along the Platte in 
Kearney county; Long Pine; Holt creek in Holt county. 
3. Equisetum robustum A. Br. Stout Scouring-rush, Big Horse-tail. 
Common along streams throughout the state. Bellevue; Brownville; 
Kearney; Kearney county; Ponca; Plummer Ford; Ft. Niobrara; 
Pine Ridge; South Bend; Squaw canyon north of Harrison. 
4. Equisetum levigatum A. Br. Smooth Scouring-rush, or Horse-tail. 
Common in wet soil, especially in clay soil along rivers. Ashland; 
Crete; Dundy county; Callaway; Fairbury; Halsey; Hat Creek 
basin; Long Pine; Lincoln; Pine Ridge; Ponca; Red Cloud; Weep- 
ing Water; Thedford; Squaw canyon. 
5. Equisetum variegatum Schleich. 
Hooker county; Kearney; Lincoln; Long Pine; Valentine. 
Phylum IJ. LEPIDOPHYTA. 
Class LIGULATAE. 
SELAGINELLALES. 
1. SELAGINELLACE. 
1. Selaginella. 26. 
1. Selaginella rupestris (L.) Spring. Little Club-moss. 
Locally abundant in gravelly soil or on rocks. Cheyenne county; 
Lincoln county; Long Pine; along Verdigris creek north of Royal. 
Has persisted for over ten years when planted in sandy soil in a 
“be in Antelope county, and in an abandoned gravel pit north of 
incoln. 
