93. LEMNACE. 339 
2. Arum Linn. 
1. A. maculatum (L.); 1. all radical hastate-sagittate green or 
spotted with purple, spadix clubshaped straight obtuse shorter 
than the spath.— E. B. 1298.—Root tuberous. L. with branch- 
ing veins. Spath large. Spadix with ovaries at the base ; above 
them whorls of anth.; above these a few filaments, probably 
abortive ovaries; club naked. Berries scarlet, remaining after 
the rest of the plant has disappeared.— Hedge-banks and thickets. 
P.IV.V. Cuckow-pint. 
Order XCITI. LEMNACEA. 
Fl. moneecious, 2, in a spath but without a spadix, solitary. 
Perianth 0. Stam. 1—2, distinct. Ovary l-celled. Style short. 
Stigma simple. Fr. bladdery, not bursting. Seeds with a coria- 
ceous ribbed testa.—Floating, frondose, no distinction of st. or 
leaf. 
1. Lemna. Spath membranous, urceolate. Stam. 1—2. 
Anth. 2-celled, didymous (cells bilocular?).—FI. from just 
below the edge of the frond. Increasing chiefly by buds. - 
1. Lemna Linn. Duckweed. 
1. L. trisulca (L.) ; fronds thin pellucid elliptic-danceolate tailed 
at one end serrated at the other, roots solitary.—E. B. 926. 
R. vii. 19.—Roots tipped with a sheath. Fronds half an in. long, 
proliferous at right angles. “Filaments recurved, filiform.” 
Schleid. Plants truly annual, producing gemme which survive 
the winter as in the other species. Stagnant water. A. VI. 
2. L. minor (L.); fronds obovate compressed opaque, roots 
solitary.—E. B. 1095. R. vii. 15.—Fronds 1—2 lines long, nearly 
flat beneath, of a compact texture. “ Filaments recurved, fili- 
form.” Schleid.—Stagnant water. A. VI. VII. 
3. L. polyrrhiza (L.); fronds roundish-obovate compressed, 
roots numerous clustered.— FE. B. 2458. R. vii. 17. Spirodela 
Schleid., Endl.—Fronds half an in. long, green above, purple be- 
neath. “ Filaments narrowed below.” Schleid.—Stagnant water. 
A. FI. have not been seen in Britain. 
4. L. gibba (L.); fronds obovate nearly flat above hemispheri- 
cal and spongy beneath, roots solitary 4#—£. B. 1233. R. vii. 16. 
Telmatophace Schleid., Endl—Fronds 1—2 lines long, remark- 
ably gibbous and cellular beneath. “‘ Filaments recurved, dilated 
in the middle.” Schleid. See an excellent account of the germi- 
nation of this plant, by Mr. Wilson, in Bot. Mise. i. 145. t. 42,— 
Stagnant water. A. VI.—VIII. 5 
a 
