6 ESSENTIALS OF BOTANY 
8. Examination of the Bean. — Study the seed, both dry and after 
twelve hours’ soaking, in the same general: way-in which the squash 
seed has just been examined.! 
Notice the presence of a distinct plumule, consisting of a pair of 
rudimentary leaves between the cotyledons, just where they are 
joined to the top of the hypocotyl. In 
many seeds (as the pea) the plumule 
does not show distinct leaves. But 
in all cases the plumule contains the 
growing point, the tip of the stem from 
which all the upward growth of the 
plant is to proceed. 
Make a sketch of these leaves as they 
lie in place on one of the cotyledons 
after the bean has been split open. 
Note the cavity in each cotyledon 
caused by the pressure of the plumule 
and of the hypocotyl.? 
4, Germination of the Grain of Corn. 
— Soak some grains of corn and plant 
them as directed in Sect. 1.8 
Make six or more sketches at various 
stages to illustrate the growth of the 
plumule and the formation of roots; 
first a main root from the base of the 
embryo, then others more slender from 
the same region, and later on still 
Fic. 2. Young Seedling of others from points higher up on the 
Windsor Bean. stem. The student may be able to dis- 
¢, cotyledon; 7, root; s, stem. cover what becomes of the large outer 
1 The Jarger the variety of bean chosen, the easier it will be to see and 
sketch the several parts. The large red kidney bean, the horticultural béan, 
or the Lima bean will do well for this examination. 
2 The teacher will find excellent sketches of most of the germinating 
seeds described in the present chapter in Newell’s Outlines of Lessons in 
Botany, Part I. 
8 The pupil may economize space by planting the new seeds in boxes 
from which part of the carlier planted seeds have been dug up for use in 
sketching, etc. : 
