THE INFLORESCENCE AND FLOWER. 



37 



their edges, so that, if you pull one, the whole calyx 

 comes off. 



When the petals of a corolla are distinct from each 

 other, so that one can be pulled off without disturbing the 

 rest, it is a polypetalous corolla, as shown in Fig. 122, 

 where pp are the distinct petals. 



When the petals of a corolla are 

 more or less grown together, so that if 



FIG. 122. Pclypetalous Corolla. 



you pull one the whole corolla comes 

 off, it is a gamopetalous corolla (Fig. 



I2 3)- 



When the leaves of a perianth are 



entirely separate from each other, it is described as poly- 

 phyl'lous ; while, if they are grown together by their edges, 

 however slightly, they are gamophyl' lous. 



Take time carefully to compare the flower-envelopes 

 of your specimens with these pictures and definitions. 

 You can count the petals of gamopetalous corollas, when 

 other ways fail, by observing their marks of union. Be 

 cautious about calling a corolla polypetalous until you have 

 examined several specimens of the same kind of flower. 

 Above all things, do not guess. If you can not decide the 

 point, consult with fellow-learners about it. 



Another important feature of flowers is their regularity. 

 A regular calyx, corolla, or perianth, has all its parts of the 

 same size and shape (Figs. 114, 115). 



