THE FLOWERING PLANTS. 15 



THE FLOWERING PLANTS. 

 The Dicotyledonous Angiosperms. 



/ 1. Soak seeds of the Bean, Pea, Squash, Mustard, Buck- 

 wheat, and Flax in water over night. Then cover them 

 half an inch deep in sawdust kept moist, not drenching 

 wet, and in a warm, light place, until they germinate 

 and grow into little plants from one to three or four 

 inches high. Other seedlings of these plants may be 

 grown in moist earth. If the earth has been previously 

 baked, growths of weeds will give less trouble. It is a 

 good plan to make several plantings, at intervals of a few 

 days, to secure plants at various stages of development. 



2. Make examinations of the little plants from the 

 time the seed coats, or outer coverings of the seeds, begin 

 to split open until the plants have attained considerable 

 size. Represent them by outline drawings in the different 

 stages of development. Do the seed coats all split open 

 in the same way ? What becomes of the seed coat ? Of 

 how many parts does the portion within the seed coat con- 

 sist ? Do these parts the cotyledons remain under- 

 ground, or are they raised above its surface ? Do you find 

 any evidence that a plant does work? Are the cotyle- 

 dons of seeds generally raised above ground ? How many 

 instances do you know of in which they are not ? The 

 portion of the stem that holds the cotyledons above ground 

 is the hypocotyl. The cotyledons are modified leaves ; 

 they are storehouses of nourishment for the first growth 

 of the plant. Does the rapidity of the first growth appear 

 to depend upon the amount of nourishment stored up in 

 the cotyledons ? Watch the cotyledons as the plants 

 become older ; do they develop ? If not, what does be- 

 come of them ? Plants in which the cotyledons expand 

 equally in the first growth are called Dicotyledons. 



