372 THE BIOLOGY OF THE PLANT 



JSTote the calyx-tube and the limb or border. 

 How do they differ ? What is the diameter of 

 the tube ? Depth ? The length of the lobes 

 of the limb 1 Width ? Is their size constant ? 

 How many lobes are there ? Is the number con- 

 stant ? What position have these lobes in a bud? 

 Why ? Is it different in the expanded flower ? 

 Why? Note the character of the surface and 

 margins of the parts of the calyx. Look for 

 nectar in the calyx. What is its color ? Con- 

 sistence ? Taste ? Why is it in this part of the 

 flower ? Do you find any elsewhere ? What is 

 its use ? Why is the base of the calyx cup- 

 shaped ? Of what use is the calyx ? What be- 

 comes of the calyx as the flower becomes older 

 and the fruit begins to form ? Do you find m 

 the ripe fruit any trace of the calyx ? Are the 

 parts of the calyx at all leaf -like in character ? 

 Draw a calyx as seen from above and as seen 

 in longitudinal section. 

 (h) The corolla or colored part. — What position 

 does it occupy in the flower ? What is its gen- 

 eral shape ? Of what use is the shape ? Of 

 how many parts or petals does the corolla con- 

 sist ? Does the number vary in different flow- 

 ers? How does the number of petals corre- 

 spond with the number of sepals ? To what 

 other parts are they attached ? In what nian- 

 ner ? What is their shape ? Size ? Color ? Are 

 all of the same shape? Of the same color? 

 What is the use of the color ? What is the char- 

 acter of the surface and margins of the petals ? 

 Of the apex, and base or claw ? What is the 

 structure of a petal? What position have the 



