254 ON SEEDLINGS 



strongly involute placentas, thus making the ovary more or 

 less distinctly four-celled, each cell with a single ovule. In 

 other cases the ovary is four-lobed and four-celled, with 

 the central part entire and together with the gynobasic 

 style persistent. It more rarely happens that the lobes are 

 connate in pairs, and each two-celled, or that there are two 

 lobes, each containing one ovule. The ovules are erect, oblique 

 or horizontal, and inserted at the base or towards the apex of 

 axile placentas. The micropyle is superior or faces the axis. 

 The fruit is drupaceous, and two- to four-celled with a woody 

 endocarp, or breaks up into two to four pyrenes, or fewer 

 by abortion. In these cases the exocarp is fleshy, baccate or 

 thin. There are many familiar instances where the fruit 

 breaks up into four nutlets, or fewer by abortion, with a hard 

 or sometimes fleshy exocarp or shell, one-seeded and in- 

 dehiscent. The seed like the ovule is erect or oblique, rarely 

 horizontal, straight or incurved, and conforming to the ulterior 

 of the cells, pyrene, or nutlet as the case may be. The 

 testa is membranous. Endosperm is copious and fleshy, or 

 scanty, and at other times entirely wanting. The embryo 

 is straight or curved in conformity with the seed, while the 

 cotyledons vary greatly, being flat, plano-convex, thick and 

 fleshy, and entire. A few cases occur where the cotyledons are 

 bifid, and others where they are much plaited. The radicle is 

 generally short and superior, or facing the axis. 



The cotyledons are plaited in the tribe Cordieae, bipartite 

 in the genus Amsinckia, and the radicle is subinferior in some 

 members of the subtribe Cynoglosseae. 



The plaited character of the cotyledons is well shown by 

 Cordia subcordata (fig. 534). The folds are longitudinal and 

 deep, causing the cotyledons to be toothed or notched at the 

 apex. The fruit is undivided, nut-Like and four-celled, but 

 three out of the four cells are usually empty or contain aborted 

 ovules only. The endocarp is woody or bony, elevated on its 

 outer surface into longitudinal and transverse ridges, and 

 covered by a fleshy exocarp, becoming cortical when dry. 

 The plaiting of the cotyledons in the nut of C. subopposita 

 is less deep and perhaps more irregular. A section shows 

 two small and two large but empty cells, while a fifth con- 



