Materials for a Flora of the Malayan Peninsula. 3 



I. HYDEOCHAEIDEAE. 



Aquatic lierbs, stem short, stolonit'erons or elongate leafy. 

 Leaves linear lanceolate or broadly ovate. Flowers regular usually 

 unisexual inclosed in a spatlie. Perianth usually of two whorls, 

 sepals 3, petals when present 3 white or yellow, stamens 3 to 12, fila- 

 ments short. Ovary inferior one-celled, placentas parietal 3-6, style 

 divided, ovules numerous. 



An order of about 50 species extending all over the world. 



Freshwater, stems long and leafy. 



Leaves whorled . . . . . . 1. Hydrilla. 



Leaves alternate . . . . ... 3. Enliydrias. 



Stem short leaves radical. 



Flowers small, petals linear . . 3. Blyxa. 



Flowers large, petals ovate . . 4. Ottelia. 



Marine, rhizome creeping. 



Leaves linear. Male flowers very nu- 

 merous in the spathe . . . . 5. Enhalus. 

 Leaves ovate. Male solitary . . . . G. Halophila. 



1. Hydrtlla, L. C. Eich. 



Submerged stem elongate branched leafy. Leaves short in 

 Avhorls of 3 or 4, or lower ones opposite. Flowers unisexual, solitary 

 in axillary spathes. Male shortly pedicelled. Sepals ovate, petals 

 narrower. Stamens three, anthers ovate two-celled. Female sessile, 

 spathe tubular. Perianth as in the male but segments narrower. 

 Ovary enclosed in the spathe except the long beak. Styles 3 rarely 

 2 linear. Fruit narrow, seeds oblong. 



A single species occurring in Tropical Africa, Mascarene Islands, 

 Asia and Australia. 



Hydrilla verticillata, Presl. Bot. Bemerk. 112. Stem 6 

 inches to a foot long, slender. I^eaves \ inch long oblong acute 

 denticulate. Hook, fib Fl. Brit. Ind. V. p. 659. Eoyle 111. Bot. 

 Himal. 3T6. Serpicvla verticiUata Eoxb. Corom. PI. t. 164. 



Eare, Kelantan in the river at Kamposa (Eidley). 



2. Eniiydrias, Eidl. 



Stems elongate branched leafy. Leaves alternate narrow linear. 

 Flowers solitary base enclosed in a tubular spathe hermaphrodite. 

 Perianth tube long slender. Calyx lobes lanceolate acute 3. Corolla 

 lobes much longer linear. Stamens three adnate to the mouth of the 

 corolla tube short, anthers linear, 2 celled. Styles 3 shorter than the 



