CXIII. EQUISETACE^E. 
600 
[ Equisetum . 
3. E. arvense L. ( corn H.) ; frond attenuate upwards, barren 
stem slightly scabrous with 12-14 furrows, branches simple 
ereeto-patent, teeth of their sheaths 3 — 4 lanceolato-subulate 
1 -ribbed to the apex, fertile stem with its sheaths remote loose. 
E. B. t. 2020 : Newm. p. 77. 
Corn-fields and road-sides, frequent. y. 4. — The sheaths of the 
fertile fronds have the nerves of the teeth deeply furrowed, so as to 
resemble two nerves. 
** Fertile stems similar to the barren ones, simple or branched. 
4. E. sylvdticum L. (branched Wood H.) ; barren and fertile 
stems with about 12 furrows, sheaths lax with about 3 or 4 
long membranous obtuse teeth, branches compound whorled 
deflexed their sheaths with 3 subulate long teeth each 1 -ribbed to 
the apex, catkin terminal obtuse. E. B. 1. 1874 : Newm. p. 59. 
Moist woods, hedge-banks; abundant in the north. y. 4, 5 . — 
A graceful species, less rigid and more herbaceous than any of the 
following. Stems annual. Sterile plants pyramidal in their outline; 
fertile ones abrupt at the top, especially after the fructification has 
passed away. 
5. E. limosum L. (smooth naked II.) ; stems nearly smooth 
striate, strise about 16 — 18, teeth of the sheaths short rigid 
distinct, branches nearly erect simple whorled often abortive, 
catkin terminal upon the stem. E. B. t. 929. E. fluviatile 
Newm. p. 51. — a. stems quite smooth, branches short and rigid 
nearly equal throughout as long as the internodes, spike nearly 
sessile. E. limosum Fries. — j3. stem somewhat scabrous above, 
branches long slender tapering to the point longer than the in- 
ternodes, spike stalked. E. fluviatile Linn. : Fries. 
Lakes, sides of rivers and pools; frequent, y. 6,7 . — Stems 
annual. Next in size to our E. Telmateia, but very different; it has 
fewer angles and teeth and fewer branches in a whorl, and these latter 
are often short and imperfect, or wanting ; differing, too, by the 
catkins being upon stems that are similar to the barren ones. Mr. 
Baker, in Phytol. iv., p. 1118, describes and figures a double row of 
tubes in the substance of the tubes of the stems in var. a. ; one row 
in /3. Mr. Newman (Br. Ferns, ed. 2, p. 7) appears to be of 
opinion that the E. limosum Linn, prefers boggy or muddy localities 
to actual water, and never under any circumstances becomes branched. 
If this view be correct, our var. a. ought to be limited to the perfectly 
simple forms, while the others would be conjoined with our f). : but 
we find both growing intermingled and otherwise undistinguishable 
by the eye. 
6. E. palustre L. (Marsh H.); stems deeply 4 — 8-furrowed, 
teeth of the sheaths wedge-shaped acute brown at the point 
and membranous at the margin, branches simple whorled 
gradually shorter upwards (sometimes abortive), catkin ter- 
minal obtuse. — a. vulgare; stem with 6 — 8 furrows, branches 
