360 
Naiadacese. Lemnacese, Typhacese. 
108. Naiadacese. 
534. Naias. Naiad. XXI, 21. XXII, 18. 
1. FIs dioecious. L.-sheaths with entire edges. Ls broad- 
linear (broader than the stem).—b. intermedia Wolfg. 
PI. smaller, ls narrower, sheaths with isolated teeth.— 
Stagnant water, rare; T. J. U. Z.; b. Robenhausen, 
Eschenz (Thurgau). 1 ... . major All. 2054. 
— FIs monoecious. L.-sheaths ciliate-denticulate. Ls nar¬ 
row-linear (^ 2 mm). Caulinia fragilis Willd.—As the last; 
Nyon, Roggwyl, Michelfelden, Wangen, Mammern (Lake 
of Constance). 7 minor All. 2055. 
109. Lemnaceae. 
535. Lemna. Duckweed. XXI, 17. XXII, 15. 
1. Fronds (‘-leaves”) orbicular-obovate, each with a tuft 
of 6—7 roots, reddish underneath (5—7 mm ).—Standing 
water, not common (wanting in G. T. U. W.?). 5 
polyrrhiza L. 2056. 
— Fronds each with a single root . ... 2 
2. Fronds (7 —10 mm) thin, oblong-lanceolate, narrowed 
like a petiole to one end, submerged except while flower¬ 
ing.—As the last (wanting in G. T. U. W. ?). 4 
trisulca L. 2057. 
— Fronds (2—3 mm) slightly thickened, orbicular-obovate, 
not narrowed to a petiole, always floating . . 3 
3. Fronds fairly flat on both sides.—As the last; every¬ 
where. 4.minor L. 2058. 
— Fronds flat above, very convex underneath.—As the last, 
but rare; W. Y. Z. 4 . . . gibba L. 2059. 
110. Typhaceae. 
536. Typha. Reedmace. XXI, 30. 
1. Caul. Is reduced, almost scale-like (in an autumnal 
form = T. Martini Jord. often as long or longer than 
the inflorescence). Fr. without a longitudinal furrow. 
Stem 4—10 dm. T. minima Hopp. — Water-side; not 
common (wanting in S.). 5 . Laxmanni Lepech. 2060. 
— Caul, ls longer than the stem. Fr. with a longitudinal 
furrow . . . .' . . . . 2 
2. The 2 spikes of the inflorescence rather distant from 
one another. Stig. linear. Ls 4—8 mm broad. Fem. spike 
brown-red. T. media Schl. (larger form).—Water-side, 
ditches; W. B. J. L. Z. S. 6 . angustifolia L. 2061. 
