70 A FIjORA of MANILA 



Abundant in the Mariquina River at Pasig; in shallow water in lakes 

 and still streams throughout the Philippines. New Guinea. 



3. OTTELIA Persoon 



Submerged herbs in fresh water. Leaves crowded, the submerged ones 

 often narrow, the floating ones long-petioled, with broad blades. Flowers 

 solitary, sessile, on a tubular, 2-fid spathe. Sepals linear or oblong. Petals 

 large, obovate or orbicular, the base with fleshy appendages. Stamens 6 to 

 15. Ovary oblong, beaked, almost 6-celled; styles 6, linear, 2-fid; ovules 

 many. Fruit oblong, 6-valved, enclosed in the spathe. 



Species 6 or 7, tropical and subtropical, 1 in the Philippines. 



1. O, alismoides (L.) Pers. Calaboa (Tag.). 



Roots fibrous. Leaves extremely variable, short- or long-petioled ac- 

 cording to the depth of the water, the blades of the submerged leaves often 

 narrow, of the floating ones ovate to suborbicular, 5 to 20 cm long and wide, 

 base rounded or often cordate. Flowers white, about 2 cm long. Fruit 

 oblong, crowned by the withered perianth, 2.5 to 4 cm long, the enclosing 

 perianth-tube winged. 



Abundant in the Mariquina River near Pasig, and in various f resh^water 

 esteros; throughout the Philippines in shallow lakes and in still streams. 

 Tropical Asia to Australia. 



4. HALOPHILA Thouars 



Slender, submerged, monoecious or dioecious, marine plants. Leaves in 

 pairs at each node of the slender creeping stem, ovate to oblong. Spathes 

 of both sexes small, solitary, sessile between the pairs of leaves, 1-flowered. 

 Male flowers pedicelled. Sepals 3. Petals none. Anthers 3, subsessile. 

 Female flowers sessile. Sepals 3. Ovary 1-celled. Styles 3, filiform. 

 Ovules several or many. Fruit subglobose, beaked. (Greek "salt" arid "to 

 love" from habit of growth in salt water.) 



Species, 6 or. more, tropical seas of both hemispheres, at ^least 3 in the 

 Philippines. 



Leaves ovate-elliptic, 4 to 5 mm wide 1. H. ovata 



Leaves linear-oblong to lanceolate, about 2 mm wide 2. H. beecarii 



1. H. ovata Gaudich. 



A very slender, prostrate, creeping, submerged, marine plant, the stems 

 branched, rooting at the nodes. Leaves ovate-elliptic, thin, obtuse, about 10 

 mm long, 4 to 5 mm'wide, the petioles slender. Flowers small, solitary, 

 monoecious or dioecious, the staminate ones pedicelled, the stamens 3, the 

 pistillate ones sessile, the perianth -small, 3-parted. Ovary ovoid, 2 mm 

 long; styles 3, slender, about 6 mm long. Mature fruit membranaceous, 

 globoser; 2 to 2.5 mm in diameter. 



In shallow water, Manila Bay, abundant February to May, and washed 

 up on the beach in considerable quantities. Otherwise known only from 

 the. Marianne Islands. 



2. H. beecarii Aschers. 



A delicate, densely matted or caespitose submerged plant, the slender 

 stems creeping and rooting on muddy bottoms. Leaves very thin, lanceolate 

 to iinear-oblong, 0.8 to 1.5 cm long, about 2 mm wide, on long slender 

 petioles. Flowei's small, monoecious. 



