!). E . LIMOSUJI Linu. Sp. edit. ii. 1517; Milde, Moii. t. 1 5 -lG ;
Hook. Br it. Ferns, t. 8 2 ; E u g . Bot. edit. iii. t. 1803. K . Jleleo-
rharis Elirli. — Barren and fertile stems alike, erect, 2 -3 ft. long,
in. diam., with a large central hollow and 1 0 -3 0 narrow smooth
ribs with broad valleonho ; sheaths rather loose, ; |- i iu- long, with
distinct triquetrous ribs and rigid lanceolate black teeth ; branches
absent in the typical fo rm ; spike dense, oblong, obtuse, -I--;] in.
long, nearly sessile.
Var. E . Jluviatile Linn., non Smith. — Many upper nodes furnished
w ith dense whorls of short ascending simple hollow branches.
Hab. Ponds and lakes of the north temiierate and arctic zones of both
hemispheres.
Suhgenus HippocHatiE Milde.
10. E . GIGANTEUM Liiiii. Sp. edit. ii. 1517; Milde, Mon. t. 81 ;
Gard. Chron. 1888, vol. ii. t. 8 6 . E . ramosissimmn H. B. K., non
De sf. E. caracasanum DC. E . Huniholdtii Poir. E . Ma rtii Milde,
Mon. t. 20. E . pyramidale G o ldm .; Milde, Mon. t. 22. E . myrio-
chectum G. & S . ; Milde, Mon. t. 27. E . mexicanum Milde, Mon.
t. 28. E . Schaffneri Milde, Mon. t. 28. 7t'. scanden.s Pvemy.— ■
Barren and fertile stems alike, erect or snbscandent, usually 6 -8 ft.
long, but reaching 2 0 -4 0 ft., | - 1 in. diam. low down, with 2 0 -5 0
narrow square scabrous ribs with a ridge down the keel and
distinct spaces between them ; sheaths tight, -J—} in. lon g ; ribs
square, scabrous, with hardly any valleculre between them ; teeth
linear, i - J in. long, black or brown, with or without a pale margin,
rigid, d eciduous; branches copious, elongated, densely whorled,
with 6 -8 scabrous ribs ; spikes dense, oblong, apiculate, black,
subsessile.
Hab. Marshes of Tropical America from Mexico and Cuba south^Yard to
Buenos Ayres and Chili, ascending to 5000 ft. in New Granada. Here I fail to
draw any distinct line between several of Milde’s species. Both in this and the
next the branches often end in small spikes.
11. E . XYLOOH.ETÜM Metteu. F il. Le cbl. ii. 3 4 ; Milde, Mon.
t. 19. E . yiganteum Hook. 2 Cent. Ferns, t. 74. E . Lechleri Milde.
—Barren and fertile stems alike, erect, reaching a height of 10 ft.,
i - l ill. diam., with a large central hollow and 3 0 -4 0 smooth square
ribs, so crowded as not to leave any distinct valleculte ; sheaths
tight, f - l j in. lon g ; ribs square, with very narrow valleculte ;
teeth linear, rigid, black, deciduous, in. long ; branches copious,
densely whorled, usually simple, with 6 -8 triquetrous scabrous
ribs ; spike dense, black, oblong, subsessile, apiculate.
Hab. Pern, near Arica, iec/iZrr 1556 ! hima, Gaudichaud. Chili, Bess«-,
Closely allied to E . giganteum,
12 , E . BAMosissmuM Desf. El. Atlan. ii. 8 9 8 ; Milde, Mon.
t. 2 4 ; E . elongatum H. B . K. E . campanulatuin Poir. E . pannonicum
Kit. E . incanum Vauch. E . ramosum Schleich. E.
ephedroides and pallidum Bory. — Barren and fertile stems alike,
1 -4 ft. long, with a large central hollow, simple or irregularly
branched, varying from i lin. diam. with 4 - 6 ribs to in. diam.
with 2 0 -2 5 r ib s ; ribs prominent, narrow, very scabrous; sheaths
rather loose, |--J in. long, their ribs margined with a distinct lino
on cacli s id e ; teeth in. long, lanceolate acuminate from a
deltoid base, castancous, with pale edges, deciduous ; spikes dense,
ohloiig, apiculate, sessile, J- 1 in. long.
Hab. Cosmopolitan in the warm temperate and tropical zones; rare in
America. Very variable. The extremes are A'. Kit., with slender
simple densely ca-spitose stems a foot or less long, with 4— 6 ribs, and Ji. altis-
stimiiii A. Br., with stout stems 3—4 ft. long, with i —1 in. sheaths and dense
whorls of branches, simulating the small forms of ¡ligaiUeum.
13. E . SiEBOLDi Milde in Ann. Mus. Lug. Bat. i. j>. 62; Mon.
t. 25.—Barren and fertile stems alike, 1- 1^ ft. long, l - 12th to
l - 6tli ill. diam., with a large central hollow and 6 -1 0 smooth
lirominent ribs ; branches short, simple, 1-3-nato ; sheaths rather
loose, i—J- in. long including the persistent linear-subulate brown
t e e th ; ribs of sheath grooved towards the apex and bordered on
each side ; spike unknown.
Hab. Japan, Siehold. Doubtfully distinct from E . raiw.nssbnum.
14. E . DEBILE Eoxh. in Vaucli. Monog. 387 ; Milde, Mon. t. 26,
E . Vaucli. Monog. t. 10. 7t'. p«//«;« Wall. K. virgatum,
laxum, and rerticillatnm Blume. — Barren and fertile stems alike,
usually 1 -4 ft., rarely 8 -1 0 ft. long, l-1 2 tli to ^ in. diam., with
a large central hollow, simple or irregularly b ranched; ribs 8 - 2 0 ,
less prominent and not so scabrous as in E . ramusissimum; sheaths
ligh t, J - J ill. long including the lanceolate acuminate brown margined
deciduous tooth, the ribs of which are distinctly grooved on
the back upwards and distinctly margined oil each s id e ; spike
oblong, cuspidate, dense, subsessile, J - f in. long.
Hab. Tropical Asia from the Himalayas and Ceylon eastward through the
Malay Isles to Fiji. Doubtfully distinct from E. ramosissinmm.
15. B . HYEMALE Liiiii. Sp. edit. ii. 1517 ; Milde, Mon. t. 29 ;
Hook. Brit. Ferns, t. 6 4 ; Eng. Bot. edit. iii. t. 1894. E . asper-
rimitin Gilib. A', zunatum Friv. — Barren and fertile stems alike,
erect, persistent, branched at the base only, 2 -3 ft. long, in.
d iam .; central hollow la r g e ; ribs 2 0 -3 0 , flat on the top, very
scabrous; sheaths tight, I—f in. long, pale green, with a distinct
zone of black at the top and b o ttom ; teeth very deciduous, small,
connate, brown, with a membranous cusp ; spike very dense, oblong,
axiiculate, sessile, 1 -4 in. long.
Var. SclileicJilcri Milde. E . paleaceum Sclileicli. ex qiarte. E .
21oorei N ew m .; Eng. Bot. edit. iii. t. 1895.— Stems less persistent
and more slender than in the type ; ribs 8 -2 0 ; sheaths not so
tight and sometimes without the black basal ring.
Hab. North temperate and arctic zones of both liemispheres. 1 ai'.
Schleicltleri, from Ireland through Central Europe to Asia Minor.
16. E . L.EviGATUM A. Bi’. ill Sillim. Journ. 1844, 87 ; Milde,
Mon. t. 32 .— Barren and fertile stems alike, erect, persistent, very
rarely branched above the base, 1 -4 ft. long, about J in. d iam .;
ribs 2 0 -8 0 , smooth or nearly s o ; central hollow very la r g e ; sheaths
not so tight as in hgemide, -|-4 in. long, and onl)' a few of the lowest
sometimes famished with a black basal ring ; teeth deciduous,