86 
LABORATORY EXERCISES 
EXERCISE 85 
SUPPLEMENTARY PROBLEMS 
These exercises may be assigned to individuals or to groups, or 
they may be used by the class as a whole. The instructor may 
allow each member of the class to choose one or more problems 
for individual work upon which he may report to the class toward 
the end of the year, or he may grant this privilege only to those 
pupils whose general class work is above average. It is expected 
that through these exercises a greater appreciation of and interest 
in nature will be developed. 
I 
DEVELOPMENT OF THE LILAC BUD 
Use a lilac shrub on the school grounds or your home grounds 
for the purpose of making these observations. Begin the observa¬ 
tions before the buds have begun to open in the spring. (Buds of 
various other plants might be studied in the same manner.) 
I. Note the size, the shape, and the color of the lilac buds as they 
appear in early spring. What is their arrangement on the stem? 
Remove the outer scales of a well developed bud. Note their 
number, size, shape, and color. To what are these scales attached? 
Next examine the tiny leaves within. To what are they attached? 
How do they differ from the outer scales? Make drawings to 
illustrate what you have seen. 
II. Select several buds of the shrub which you observe. Mark 
the twig on which these are found. (This may be done by tying 
a string around it.) Note the changes which occur from day to 
day. What becomes of the outer scales? What has been their 
function? Note the scars which remain when these fall. Observe 
carefully the way in which the inner portions grow and into what 
each structure develops. Whaf? becomes of the central axis of the 
bud? Make very frequent sketches of the plant which will show 
the manner of development. Date each. 
