14'> NATURAL HISTORY OF PLANTS. 



two stylary branches of variable length, with pointed or obtuse stig- 

 matiferous extremity. High in the internal angle of each ovarian 

 cell is inserted a descending anatropous ovule, with micropyle 

 directed upwards and outwards.' The fruit (fig. 160, 161) is a 

 diaehene, sometimes at first a little fleshy on the surface, shortly oval, 

 or nearly orbicular, or didymous, and very much compressed per- 



Sydrocotyle asiaiica. 



Fig. 158. Three-flowered inflorescence. Fig. 159. Long. sect, of flower ('j"). 



pendicular to the partition, often constricted at the commissure. The 

 ridges, very little developed, linear, scarcely projecting, are all 

 primary, or rather the secondary are perceptible, but very indistinct. 

 Each mericarp may therefore have as many as nine ridges, and the 

 dorsal corresponds to the margin of the fruit. They may be con- 

 nected by a network of veinules. In the thickness of the ridges, 

 there may be here and there one or two vittae, most frequently ir- 

 regular, broken or rudimentary. 



Hydrocotyle consists of plants ordinarily small, herbaceous, aquatic, 

 often perennial, rarely subshrubby at the base. The perennial species 

 generally have a slender stock creeping on the moist soil or in the 

 mud, sending out adventitious roots at the nodes. The leaves are 

 alternate, petiolate, entire, or crenelate, digitinerved or palmatisect, 

 not unfrequently peltate, rarely narrow and elongate, uninerved. 

 They are accompanied at the base by scarious stipules,^ entire or 

 laciniate, sometimes none. The flowers,' hermaphrodite or poly- 

 gamous, are arranged in a very variable manner at the nodes of the 

 stem or at the end of the branches. One or many peduncles from the 



' Ordinarily without a true coat or with only ' Their stipular nature has been disputed; 



a slight rudiment. ' Small, greenish, yellow or reddish. 



