LOASE^E 



579 



late. Endosperm is absent or present in variable quantity 

 and fleshy or very rarely horny. The embryo is straight or 

 hooked as in Mentzelia, and linear, oblong, or terete with 

 plano-convex foliaceous or hemispherical cotyledons, and a 

 short or elongated radicle. When endosperm is wanting the 

 cotyledons are fleshy. The ovule is solitary in Petalonyx, 

 Gronovia and Cevallia, and when it has changed to a mature 

 seed it conforms to the single cavity of the ovary. In a few 

 species of Loasa the seeds are large, globose or oblong, with a 

 horny albumen and minute embryo. 



Seedlings. The cotyledons, like the seeds, differ consider- 

 ably. Those observed vary between roundly or broadly ovate 

 and oval, and are generally emarginate. 



Loasa prostrata, Gill. (fig. 370). 



Hypocotyl 4-6 cm. long, erect, terete, covered with numerous 

 hairs, some of which are much longer than the rest, and stinging, 

 almost colourless. 



Cotyledons broadly and ovately oblong, 

 obtuse, entire, shortly petiolate, mem- 

 branous, hairy with many stinging hairs, 

 light green, five-nerved. 



Stem erect, terete, herbaceous, hairy ; 

 1st internode 5-6 mm. long. 



Loasa lateritia, Gill, et Hook. (fig. 

 371). 



Primary root tapering downwards, long, 

 slender and rather sparingly furnished 

 with lateral rootlets. 



Hypocotyl erect, terete, pale green, 

 almost colourless, hispidly pubescent, 5-7 

 mm. long. 



Cotyledons smaU, rotund, emarginate, petiolate, thinly hispidly 

 pubescent, pale green above, paler beneath, with a midrib discernible 

 only by transmitted light ; lamina 2-2-5 mm. long and wide ; 

 petiole flattened or slightly grooved above, convex below, -5-1-5 mm. 



Stem herbaceous, ultimately twining ; primary internodes unde- 

 veloped. 



Leaves simple, radical and cauline, opposite (or at least the lower 

 ones), exstipulate, petiolate, hispidly pubescent and coarsely hairy 



p p 2 



FIG. 370. Loasa prostrata- 

 Half nat. size. 



