, 
SprropELA.] LEMNACEX. 305 
1. SPIRODELA, Schleid. Under Lemna Fl. Brit. Ind. vi, 556. 
Fronds with several roots, the basal portion with two lateral 
pockets from one or both of which daughter shoots arise, these 
remaining united with the parent or becoming detached. Flowers 
appearing on the less vigorously growing side of the shoot, starting 
with a delicate ventral leaf (spathe) followed by a pair of anthers 
and a pistil. Anthers in an early stage 4-celled but soon appear- 
ing 2-celled. Ovary with 2 anatropous ovules. Species 2, one 
Indo-Malayan, the other widely distributed. 
S. polyrrhiza, Schleid. Lemna polyrrhiza, Linn., Fl. Brit. Ind, 
vi, 557; Prain Beng. Pl. 1117; Cooke, Fl. Bomb., ii, 832. L, 
orbiculata, Roxb. Fl. Ind. wi, 565.3 
Fronds }-4 in. long, broadly obovate or orbicular, rather thick, dark 
green above usually purplish beneath, roots several, up to 16, in a 
fascicle towards the basal end of the fronds. Spathe 2-lipped. 
Dehra Dun (Parker) growing with Azolla pinnata, R. Br. 
Distris.: Temperate and tropical regions. 
S. oligorrhiza, Hegelm. Lemna oligorrhiza, Kurz, with thinner narrower 
fronds and 2-5 roots may also occur. It is common in Bengal, 
2. LEMNA, Linn.; Fl. Brit. Ind. vi, 556, ex parte. 
Fronds with a single root. Ovary with 1-6 anatropous, semi- 
anatropous or orthotropous ovules. Otherwise as for Spirodela, 
Species 5 in tropical and temperate regions. . 
Fronds entire, branches soon detached . . IL. L. paucicostata. 
Fronds serrulate at the tip, branches hastate 
persistent ‘ ‘ : , ; . 2. L. trisulea, 
1. L. paucicostata, Hegelm. Fl, Brit. Ind, vi, 556; Prain Beng, 
Pl. 1117. 
Fronds about } in. long, oblong or obovate-oblong, somewhat oblique 
at the basal end, rather thin, nearly flat on both sides. Root-sheath 
with a minute wing on either side at the base, root-cap acute: 
Ovule soktary, orthotropous, 
Cc 
