26 



ON SEEDLINGS 



glabrous, pale green ; 1st, 2nd, and 3rd internodes undeveloped ; 

 4th 5'5 mm. ; 5th 9 - 5 mm. long. 



Leaves simple, radical, alternate, exstipulate, petiolate, glabrous, 

 peltate, orbicular, crenate. 



No. 1. Orbicular, entire, or obscurely crenate, or frequently 



FIG. 405. Hydrocotyle vulgaris. Nat. size. 



dentate, sometimes reniform, or if orbicular with a more or less 

 open sinus and not peltate, obscurely five-nerved. 



No. 2. Peltate, seven-nerved and shallowly crenate. 

 No. 3. Similar but larger. 



Ultimate leaves orbicular, peltate, seven- to nine-nerved, and 

 lobulate-crenate or doubly crenate, glabrous and bright shining 

 green above, paler beneath, and very thinly hairy or glabrous ; 

 A veins slightly branching 



and reticulate towards the 

 apex ; petioles variable hi 

 length according to posi- 

 tion and moisture, terete, 

 hairy near the top, other- 

 wise glabrous. The plant 

 grows in marshy places. 



FIG. 406. Trachymene pilosa, x 10. 

 A, longitudinal section of mericarp. B, trans- 

 verse section : E, embryo ; PC, pericarp ; OT, 

 testa; IT, tegmen; En, endosperm; C, coty- 

 ledons. 



Trachymene 

 Sm. (fig. 406). 



pilosa, 



Fruit a cremocarp of 

 two mericarps ; commis- 

 sure very narrow ; meri- 

 carps laterally compressed. 

 Seed laterally much compressed, flat, conforming to the fruit. 

 Embryo minute, straight ; cotyledons rounded, short and com- 

 paratively broad, lying in the broad plane of the seed with their 

 edges to the placenta, plano-convex ; radicle very short, blunt. 

 This position of the embryo is very exceptional in the Order. 



