OLEACE/E 



213 



Fruit a two-celled capsule, dehiscing at the apex, one seed in 

 each cell. 



Seeds oblong, smooth, winged, laterally flattened, 8-10 mm. long ; 

 hilum inconspicuous, basal. 



Endosperm copious, fleshy, white, surrounding the embryo. 



Embryo straight, nearly equal in length to the endosperm, 

 colourless ; cotyledons oval, obtuse, entire, rather narrow, plano- 

 convex ; radicle terete, obtuse, slightly shorter than the cotyledons, 

 close to the hilum and pointing to the upper end of the seed. 



Fraxinus excelsior, L. (fig. 511). 



Ovary two-celled, each cell two-ovuled ; ovules pendulous from 

 the top of the cells, anatropous ; micropyle superior. 



Frwt a samara, linear-oblong, obtuse, nearly always obliquely 

 emarginate, laterally much compressed and thin, produced at the 

 apex into a thin wing, glabrous, striated 

 longitudinally with nerves, one-celled by 

 the rupture of the septum, one-seeded 

 by abortion, indehiscent ; septum in the 

 narrow way of the fruit, soon becoming 

 ruptured and bearing at its apex three 

 aborted ovules and one fertile seed. 



Seed oblong, obtuse, slightly narrowed 

 at both ends, much compressed laterally, 

 thin, striated or shallowly furrowed lon- 

 gitudinally, deep brown, conforming in 

 shape to the interior of the fruit, sus- 

 pended from the apex of the septum or 

 placenta by a curved funicle which is 

 persistent ; raphe dorsal, passing round 

 the dorsal edge to the chalaza at the 

 apex of the seed ; micropyle and radicle 

 superior. 



Endosperm copious, fleshy, pale or 

 colourless, and subtransparent. 



Embryo straight, flat, comparatively 

 small, embedded in the endosperm at the 



upper or basal end of the seed ; cotyledons oblong, obtuse, entire, 

 narrowed somewhat to the base, flat, closely adpressed, face to face ; 

 radicle stout, obtuse, somewhat shorter than the cotyledons, close 

 to the micropyle at the upper end of the seed, but within the endo- 

 sperm. 



FIG. 511. Fraxinus excel- 

 sior. A, samara with half 

 removed and the seed pulled 

 out (nat. size):^>a, placental 

 axis ; ao, aborted ovules ; 

 /, funicle; ra, raphe; 

 ch, chalaza. B, longitu- 

 dinal section of seed, x 2 : 

 /, funicle ; p, endosperm ; 

 e, embryo ; ra, raphe ; ch, 

 chalaza. 



