590 LXII. ONAGKACEJE. (C. B. Clarke.) [Trapa. 



5. TRAP A, Linn. 



Floating herbs. Leaves dimorphic ; submersed opposite, root-like, pinnati- 

 partite, with filiform segments ; emersed rosulate, rhomboidal, the petiole with 

 a spongy dilatation near its apex. Flowers axillary, solitary, peduncled. Calyx- 

 tube short, aduate to the lower part of the ovary; limb 4-partite, 2 or all the 

 segments persistent and becoming spinescent on the fruit. Petals 4, white, 

 small, inserted at the margin of an epigynous disc. Stamens 4. Ovary half- 

 inferior, with a conical vertex, 2-celled; style subulate, stigma capitate; ovule 

 solitary in each cell, pendulous from the upper inner angle. Fruit bony, 

 1-celled, large, obovoid, with 4 angles, 2 or all of which carry spines, indehis- 

 cent, with a short cylindric beak at the top through which the radicle is pro- 

 truded. Seed 1, inverse, cotyledons very unequal. DISTRIB. Species 2, ex- 

 tending through the warmer parts of the Old World, from Central Europe to 

 China and to Tropical Africa. 



1. T. bispinosa, Roxb. Cor. PL 234; Hort. JBeng. 11 ; Fl. Ind. i. 428; 

 leaves usually very villous beneath, fruit with 2 angles spinescent. DC. Prodr. 

 iii. 64; Wall. Cat. 6339; W. $ A. Prodr. 337; Miq. Fl. Ind. Bat. i. pt. i. 

 636 ; Dais. '$ Gibs. Bomb. Fl. 99 ; Kurz in Journ. As. Soc. 1877, pt. ii. 91. T. 

 quadrispinosa, Wall. Cat. 6340 not Roxb.Rheede Hort. Mai. xi. t. 33. 



Throughout INDIA and CEYLON. DISTEIB. South-eastern Asia and Malaya ; Tro- 

 pical Africa. 



In the Koxburghian type, floating leaves 2 by 2^-3 in., very villous beneath, pos- 

 terior margin entire, anterior lightly crenate ; petiole 4-6 in., woolly. Fruit '% in. 

 long and broad, glabrous or hairy ; two opposite angles each with an often retrorsely 

 scabrous spine, the other two angles sometimes obsolete. Very doubtfully distinct 

 from the next species as Wallich has noted on his specimens. 



VAR. inc-lsa, Wall. ; leaves much smaller about ^ in. much less villous beneath 

 incise serrate on the anterior margin. Marked also T. quadrispinosa by Wallich ; 

 but though the leaves are the leaves of T. natans, the fruit is that of T. bispinosa. 



2. T. natans, Linn. ; DC. Prodr. iii. 63 ; leaves sparingly villous on the 

 nerves beneath, fruit with all 4 angles carrying spines. Lamk. Itt. t. 75 ; Boiss. 

 Fl. Orient, ii. 753. T. quadrispinosa, Roxb. Hort. Beng. 11 ; Fl. Ind. i. 451 ; 

 DC. I. c. 



KASHMIR; Falconer, Jacquemont. SILHET; Roxburgh (but no example thence at 

 Kew). DISTRIB. Persia to Central Europe and the Upper Nile. 



Floating leaves 1 in., dentate or incise-dentate on the anterior margin; petiole 

 2-4 in., glabrescent. Fruit f in. broad, the 4 angles all spinescent but the two lateral 

 spines shorter. 



ORDER LXIII. SAMYDACEJE. (By C. B. Clarke, F.L.S.) 



Trees or shrubs. Leaves alternate, often distichous, petioled occasionally 

 subsessile, simple, entirely or lightly crenate or serrate, often closely punctulate 

 beneath; stipules small, deciduous. Flowers regular, small, axillary, shortly 

 pedicelled, densely fascicled or in long simple or panicled racemes. Calyx 

 coriaceous, persistent ; tube short, free, or longer and adnate to the ovary ; 

 limb 3-7-fid. Petals as many as the calyx-lobes (or 0), perigynous, imbricated. 

 Stamens definite or indefinite, often with staminodes between or united in a 

 tube with them. Ovary superior or half-superior, 1-celled ; style 1, capitate or 



