PHYTOLACCACE^E 



433 



Petiveria octandra, L. (fig. 616). 



Ovary of two carpels, one-celled, one-ovuled ; ovule basal, erect, 

 amphitropous ; micropyle inferior. 



Fruit an achene, oblong-linear, subcuneate, laterally compressed 

 and surrounded longitudinally with a median ridge on both sides, 

 longitudinally striated and sulcate, bifid at the apex and crowned 

 with two to six unequal-sized, closely reflexed acute bristles, more or 

 less hairy, brown ; pericarp coriaceous, closely adhering to the seed. 



Seed oblong-linear, conforming to the interior of the achene ; 

 testa membranous ; tegmen adhering to the endosperm ; hilum basal, 

 somewhat oblique ; micropyle contiguous to the hilum ; raphe none. 



Endosperm moderately copious, whitish, subfarinaceous or fleshy. 



Embryo large, surrounded by the endosperm, doubled upon 

 itself; cotyledons very unequal, and often only one, the smaller 

 being aborted ; larger one very broad, deeply cordate at the base, 

 strongly convolute and enclosing the smaller when present ; apex 

 subtrilobate, with rounded obtuse lobes, the lateral ones curving 

 round the smaller cotyledon, while the middle one is curved at the 

 apex and just within the endosperm at the apex of the seed ; inner 

 one much longer, convolute within the larger 

 one, refracted near the middle, just within 

 the apex of the endosperm and carried down 

 again nearly to the tip of the radicle ; radicle 

 stout, cylindrical, obtuse, rather long, close 

 to the micropyle at the base of the seed. 



Seedling (fig. 617). 



Primary root slender, with many colour- 

 less branched fibrous rootlets. 



Hypocotyl herbaceous, about 2 cm. long, 

 1 mm. thick, slightly ridged, pubescent, green 

 or brownish-red. 



Cotyledons very unequal, stalked, gener- 

 ally one is about 2 cm. long, 1 % 75 cm. wide, 

 subcordate, obtusely cuspidate, coarsely 

 crenate, sinuate near the apex, trinerved at 

 the base, penninerved. The other is about 

 3 cm. long, T25 cm. wide, oblong, obtuse 

 at both ends, entire, penninerved ; both are 

 glabrous except the short pubescent petioles, 

 thin, with sunk midrib, bright green, not very persistent. 



Stem herbaceous, erect ; 1st internode 6 mm. long, 1-1-5 mm. 

 thick, terete, pubescent, brown. 



FIG. 617. 



Petiveria octandra. 

 Half nat. size. 



