THE SEED 



19 



between the inner and outer layers ? Look at the base of the 

 hypocotyl for some loose, cobwebby appendages. These are 

 the remains of other embryos with certain append- 

 ages belonging to them that were formed in the 

 endosperm, but failed to develop. Did you find 

 remains of this kind in any of the other seeds ex- 

 amined? Pick out the embryo from the endo- 

 sperm and test both for food substances. Which 

 of these do you find? Which are absent? How 

 does the embryo differ from those already exam- 

 ined ? How many cotyledons are there ? Make 

 an enlarged sketch of a seed in longitudinal 

 section, labeling correctly all the parts observed. 



16. Comparison as to food value of seeds. Make in your 

 notebook a tabular statement after the model here given, of 

 the food contents found in the different seeds you have ex- 

 amined. Indicate the relative quantity of each by writing 

 under it, in the appropriate column, the words, " much," 

 " little," or " none/' as the case may be. 



By far the greater lumber of seeds contain endosperm; 



that is, they consist of an embryo with more or less nourishing 



* 



MODEL FOR RECORD OF SEEDS EXAMINED 



FIG. 29. 

 - Section of 

 pine seed, 

 showing the 

 polycotyle- 

 donous em- 

 bryo (GRAY). 



