582 LXII. ONAGRACE^E. (C. B. Clarke.) 



ORDER LXII. ON A GRACED. (By 0. B. Clarke, F.L.S.) 



Herbs, rarely undershrubs, sometimes aquatic. Leaves opposite or alternate, 

 entire or toothed, undivided (in Trapa the submersed leaves pinnatipartite), 

 exstipulate. Flowers hermaphrodite, mostly axillary and solitary, or spiked or 

 racemed towards the ends of the branches ; subirregular. Calyx-tube wholly 

 adnate to the ovary (half-adnate in Trapa), limb of 2-5 valvate lobes. Petals 

 epigynous, alternate with the calyx-lobes, rarely 0. Stamens as many or twice 

 as many as the petals, inserted with them. Ovary inferior (half-inferior in 

 Trapa), 1-6-celled, most often 4-celled ; style 1, cylindric or subulate, stigma 

 capitate or nearly 2-lobed or 4-fid ; ovules one or many in each cell, pendulous 

 or half-ascending, placentas axile. Fruit various, dehiscent or indehiscent, 

 membranous capsular or bony, 1- or several-celled, 1 or oc-seeded. Seeds with- 

 out albumen, or nearly so. DISTRIB. Species 300, spread throughout the world, 

 most abundant in the^North Temperate Zone. 



(Eiwthera is an American genus of which several species are cultivated in India : 

 and among these (E. rosea has run wild in the North-west Himalaya and in the Nil- 

 ghiris ; (E. tetraptera and (E. odorata have also run wild on the Nilghiris. 



* Seeds very many. 



f Seeds comose 1. EPILOBIUM. 



ft Seeds not comose. 



Stamens twice as many as calyx-lobes 2. JUSSIJEA. 



Stamens as many as calyx-lobes 3. LUDWIGIA. 



** Seeds one or two. 



Terrestrial. Stamens 2 4. CIJRC^EA. 



Aquatic. Stamens 4 5. TRAPA.. 



I. EPILOBSITM, Linn. 



Herbs. Leaves alternate or opposite, undivided, entire or toothed. Floivers 

 axillary and solitary, or racemed or spiked towards the ends of the branches, 

 purple 0r white, regular or irregular. Calyx-tube scarcely produced above the 

 ovary, linear; teeth 4, lanceolate, deciduous. Petals 4, obovate, retuse or 

 notched. Stamens 8, epigynous, 4 shorter. Ovary inferior, 4-celled ; style 

 cylindric, stigmas 4 spreading or more or less combined ; ovules many, axile, 

 ascending, attached along a double placental vertical line in the inner angle of 

 each cell. Capsule linear, 4-celled, dehiscing from the apex loculicidally, valves 

 4 recurved from the seed-bearing quadrangular column. Seeds very many, 

 obovoid or ellipsoid, crowned by long silky hairs. DISTRIB. Species 50 ; spread 

 throughout the temperate and cold regions of the world, plentiful in New 

 Zealand : appearing in the mountains only of the warmer regions. 



SECT. I. Chamaenerium. Flowers irregular. Stamens deflexed on one 

 side. Style bent on one side in aestivation. 



] . E. ang-ustifolium, Linn. ; Bow. Fl. Orient, ii. 745 ; leaves narrow 

 lanceolate glabrous beneath or nearly so reticulating nerves prominent primary , 

 nerves diverging nearly at right angles from the midrib, peduncles approximate 



