Wolffia. | CLI. LEMNACEZ (BROWN). 205: 
Mozamb. Dist. German East Africa: Ugogo; Ngangadra, Stuhlmann (ex. 
Hegelmaier). 
Also in Lower Egypt. 
3. W. Welwitschii, Hegelmaier in Journ. Bot. 1865, 114.. 
Frond small, 2-3 lin. long, 1-2 lin. broad, oblong, broadly or sub- 
truncately rounded at the ends, undulated or with one or more folds 
along each side, entire, very thin, almost membranous in the dried 
state, pale green, pellucid. Flowers in two cavities on the upper 
surface of the frond near the basal end on either side of the middle 
line, very minute ; ovary flask-shaped. Fruit about } lin. long, ellip- 
soid, smooth.—Hegelmaier, Monogr. Lemn. 130, t. 4, figs. 1-10, and 
in Engl. Jahrb. xxi. 300; Engl. and Prantl, Pflanzenfam. ii. iii. 164 and 
160, fig. 105, C; Durand & Schinz, Conspect. Fl. Afr. v. 485; Rendle in 
Cat. Afr, Pl. Welw. ii. 92. W. conguensis, Welw. ex Trimen in Journ. 
Bot. 1866, 221. 
Lower Guinea. Angola: Ambriz; in the lakes of Quizembo, and in lakes. 
and stagnant pools not far from the sea, between Ambriz and the mouth of the River 
Congo, Welwitsch, 209 ! 
Also in Venezuela and Cuba. 
Welwitsch appears not to have seen fruit of this species, but I have found a 
specimen with fruit among the very small quantity examined. 
4. W. Michelii, Schleid. Beitr. Bot. 233. Frond minute, }-} lin. 
long, about } lin. broad, elliptic or orbicular in outline, nearly as thick 
as broad, rather dark green. Flowers very rarely.—N. E. Br. in Dyer, 
Fl. Cap. vii. 40; Rendle in Cat. Afr. Pl. Welw. ii. 92, W. arrhiza, 
Wimm. Fl. Schles. ed. 3, 140; Journ. Bot. 1865, 113, t. 29; Hegel- 
maier, Monogr. Lemn. 124, and in Engl. Jahrb. xxi. 301; Engl. & 
Prantl, Pflanzenfam. ii. iii. 164, 154, fig. 101, D-E, 157, fig. 103, 160, 
fig. 105, A, and 106, E-F; Durand & Schinz, Conspect. Fl. Afr. v. 485 ; 
Engl. Pfl. Ost-Afr. C. 422. Lemna arrhiza, Linn. Mant. 294. Bruniera 
vvipara, Franch. in Billotia, i. 25, t. 1. 
Lower Guinea. Angola: Barra do Dande; plentiful in lakes near the banks. 
of the River Dande, near Bombo, Welwitsch, 210! and by the banks of the River 
Lifune, at Libollo, Welwitsch ! Icolo e Bengo; Lagoa de Quilunda, near Prata,. 
Welwitsch, 211. Huilla ; between Huilla and Humpata, Johnston ! 
Mozamb. Dist. German East Africa: Usaramo; Dar es Salaam, Hilde- 
brandt, 1236! 
Very widely distributed in the Eastern Hemisphere, and has been found in Brazil 
according to Hegelmaier. 
5. W. cylindracea, Hegelmaicr, Monogr. Lemn. 123, t. 1, Jigs. 14, 
15, Frond minute, about } lin. long, } lin. broad and thick, ellipsoid, 
ovoid, or subcylindric, obtuse at both ends, or somewhat pointed at the 
apex, convex on both sides, but the lower surface more SO than the 
upper, deep green, shining. Flowers unknown.—Hegelmaier in Engl. 
