THE SEED 317 
most part polygonal starch grains and oil droplets; and an inner 
mealy zone of cells with mostly rounded starch grains. 
Fic. 238.—Median longitudinal section through the lesser diameter of a grain of 
corn (Zea Mays). p, pericarp which is attached to subjacent seed coat; al, aleurone 
layer of endosperm; end, horny endosperm; fe, floury endosperm; e, epithelium of 
scutellum; sc, scutellum; cr, coleorhiza; r, radicle; pl, plumule. X 8. 
5. The Empryo, consisting of a single shield-shaped cotyledon 
adjoining the endosperm, the plumule or rudimentary bud at the 
end of the caulicle or rudimentary stem and the radicle or rudi- 
mentary root, with its tip covered by a root cap. The cotyledon 
