404 
93. EaUISETACE^. 
end ; general outline attenuated ujiwards. Fertile st. short, with 
tew (4 — 5) sheaths. Sterile and fertile st. always distinct. — 
Daraj) meadows. P. IV. 
2. E. umbrosum (Willd.); sterile st. with about 20 stria; very 
scabrous ivith prominent points jiartieularly above, branches sim- 
])le with .3 or 4 simple angles, fertile st. simple with numerous 
crowded deei>ly toothed shciiths. — N. 0.3. E. Driimmondii Hook., 
E. B. S. 2777 ■ — Sterile st. 1 — lift, high, nearly naked below, with 
numerous whorls of slender branches in the upj)er part having 
.3- or 4-toothed sheaths, each tooth blunt with one rib vanishinr/ 
upwards ; general outline remarkably obtuse at the toji. Branched 
fertile st. with larger sheaths and uhorls of about (! branches ; 
simple fertile st. short (4 — 6 in.), with numerous loose and still 
larger yellowish-white sheaths with black prominent ribs ujiwards 
and 12 — 20 teeth. — AVet places, rare. P. IV. 
3. E. Telmateia (Ehrh.)j sterile st. nearly smooth with about 
.30 striic and branches, branches rough doubly-angular simple, 
fertile st. simple with numerous crowded large deeply toothed 
sheaths. — N. 67- E. Jluviatileiim., E. B. 2022. — Sterile st. 3 — 6 
ft. high ; occasionally bearing a small terminal catkin ; furnished 
from toj) to bottom rvitb whorls of slender branches which have 
4 angles each with a longitudinal furrow, and 4-toothed sheaths 
each tooth with 2 denticulated ribs. Fertile st. stout 1 foot or 
more in height with numerous jiale brown sheaths with 30 — 40 
teeth ; catkin large. — Wet places. P. IV. 
** Sterile and fertile stems similar, simple or branched. 
4. E. sylvaticum (L.) ; sterile and fertile st. with about 12 
furrows and numerous wborls of slender compound spreading or 
deflexed branches, sheaths lax ending in 3 or 4 blunt lobes. — 
E. B. 1874. IV. 59. — St. 12 — 18 in. high. Sheaths of the branches 
with .3 long acute teeth each having a rib extending to its end. 
Fertile st. occasionally sim])le. Catkin blunt. General outline 
of sterile st. j)yramidal, of fertile abnijrt. — Wet shady places. 
P. IV. V. 
5. E. limosum (L.) ; st. smooth with many slight furrows, teeth 
of the sheaths short rigid acute, branches erect sim})le whorled 
often .abortive. — E. B. 929. — Usually growing in water. St. about 
2 ft. high, veiT smooth, simple below. Sheaths rather short. 
Catkin l)lunt. — a. limosum ; teeth of the sheaths not furrowed, 
•sheaths of the branches green with minute black tips to the round- 
backed ribs, branches often wanting. E. limosum Fries. — S- flv- 
viatile; st. more deejdy furrowed, teeth of the sheaths short dark 
brown acute : rib f arrowed on the back. E.fiuviatile (L.) Fries. 
— In stagnant water. [/3. Uejjorted to be a native.] P. VI. VII. 
