COROLLA. 



59 



Fig. 109. 



or more whorls are developed, the outer is called the calyx.. 

 the inner the corolla. 



The corolla, like the calyx, is exceedingly various in its 

 form and appearance, and therefore requires to be further de- 

 scribed and illustrated. 



When the corolla consists of only one piece, or petal, it is 

 called monopetalous, or one petaled. If it consists of more 

 than one petal, it is termed polypetalous, or many petaled. In 

 many instances monopetalous corollas appear to be polypeta- 

 lous, because their divisions reach nearly to the base, and 

 each section stands .as a distinct petal. But however deeply 

 the corolla is divided, if the petals adhere to each other at the 

 base, and there form a ring, or tube, it is monopetalous. To 

 ascertain this, it is often necessary to dissect the flower, or 

 pull it to pieces. 



A monopetalous corolla, Fig. 109, con- 

 sists of two parts ; the tube, b, or cylindrical 

 part, which is often enclosed within the 

 calyx, as in the Primrose, and the limb, a, 

 which is the spreading portion of the same 

 flower. 



The following are among the most com- 

 mon forms of this kind of corolla. 



Campanulate, Fig. 110. (Bell-shaped,) hav- 

 ing the shape of a bell, that is, it swells sud- 

 denly at the base, and has no perceptible tube 

 or elongation there. Ex. Bell-flower, (Cam- 

 panula.) 



Funnel-shaped, Fig. Ill, (Infundibuliform.) 

 It is shaped like a funnel, the base being 

 small like a tube, and gradually swelling up- 

 wards like an inverted cone. There are 

 many different varieties of this form. Ex. 

 Tobacco, (Nicotiana,) Morning Glory, . (Ipo- 

 mcea,) Henbane, (Hyoscyamus.) 



Fig. 111. 



When two or more whorls are developed, which is the calyx, and which 

 the corolla 1 When is the corolla monopetalous?. When is the corolla 

 said to be polypetalous ? What part of the corolla is the limb, and what 

 part is the tube ] What is the form of the campanuiate corolla 1 How is 



funnel-shaped corolla formed 1 



