146 FLORA OF MADRAS. [Hydrocera. 



5. Hydrocera, Blume. 



Erect aquatic herbs. Leaves narrow, alternate ; stipules 0. 

 Flowers irregular, on short axillary 1-2-flowered peduncles. Sepals 

 5, petaloid, imbricate, the 2 lateral outer flat, the posterior spurred. 

 Petals 5, anterior outermost in bud large, concave. Disk 0. 

 Stamens 5 ; filaments short, broad ; anthers connate. Ovary 

 5-celled ; stigmas 5, sessile ; ovules 2-3 in each cell. Fruit an 

 indehiscent drupe with a bony, truncate, 5-celled stone. Seed in 

 each cell solitary, curved, corrugated ; albumen ; cotyledons 

 thick ; radicle short, superior. 



HYDROCERA TRIFLORA, W. & A. 140 ; F. B. I. i. 483. 



An annual water- weed with fistular floating stems rooting at 



the nodes, linear-lanceolate leaves and red globose succulent 



fruit. 



Ditches and tanks in the Carnatic. 



Family XXXIY. RUTACEAE. 



Trees or shrubs, sometimes climbing, rarely herbs, abounding 

 in pellucid glands filled with essential oil. Leaves opposite or 

 alternate, usually compound, exstipulate. Flowers usually her- 

 maphrodite and regular, in axillary or terminal cymes or panicles, 

 never in spikes, rarely in racemes. Calyx of 4-5, rarely 3, small 

 lobes. Petals 4-5, rarely 3, hypogynous, valvate or imbricate. 

 Disk annular, crenate or lobed, sometimes elongate. Stamens 

 usually either as many as the petals or twice as many, sometimes 

 more ; filaments usually free, inserted around the disk ; anthers 

 2-celled, introrse. Ovary of 4-5, sometimes 3, sometimes more, 

 free or connate carpels ; styles as many as the carpels, free or 

 more or less connate ; stigmas terminal, entire or lobed ; ovules 

 usually 2 in each cell, sometimes numerous. Fruit a capsule 

 berry or drupe, or of 1-4 capsular cocci. Seeds usually solitary 

 in the cells, sometimes numerous ; testa various ; albumen fleshy 

 or ; embryo straight or curved ; radicle superior. 



Seeds albuminous ; flowers usually polygamous or monoecious : 

 Fruit dehiscent, of 1-5 separate 1-seeded carpels : 

 Leaves opposite ; unarmed trees or shrubs : 



Stamens 4-5 ; leaves 2-f oliolate 1 . E vodia. 



Stamens 8; leaves 1-foliolate 2. Melicope. 



