XX. 



MAIZE. 



L STRUCTURE (cON'CLUDED). 



225. The Embryo. — The scutellum and vegetative portion 

 with its miniaUire leaves and roots can readily be seen with 

 alow power microscope. (61) The embr}'o situated on the side 

 toward the tip of the ear, while variable in size, is relatively 

 large, variations of from 7.7 to 15.7 per cent having been re- 

 ported.^ In an average ear, not far from one-eighth of the grain 

 is embr}-o. (60) The embr}-o is characterized by high percent- 

 age of ash, protein and fat. The following per cents in the 

 water-free substance of the embiyo have been reported : ^ 



Voorhees 

 Balland . 

 Hopkins . 



Fat 



26.7 



39-9 

 34.8 



In dent maize the embr)-o contains about twent}' per cent of 

 the protein, sevent}--five per cent of the ash and eight^^ to eight}^- 

 four per cent of fat of the whole grain.^ 



226. The Endosperm. — A section of the endosperm varies 

 from snowy white to translucent in appearance. The difference 

 bet^veen the t}-pes or subspecies of maize is in part based upon 

 the relative amounts and arrangements of the white and trans- 

 lucent or corneous endosperm. When cross-sections of the 



1 111. BuL 55, PP- 234-235- 



8 III BuL 53, p. 140; Sj, p. 83. 



t IIL BuL 87. PP< Qo-gi. 



