26 INTRODUCTION. 



one piece or scale ; of two, three, or more pieces. It may be egg- 

 shaped, lance-shaped, keeled, acute, &c. 



II. Of the Corolla. 



The Corolla is the envelope of coloured and delicate leaves, 

 always internal with respect to the calyx, and surrounding the 

 stamens and other essential parts. The leaves or pieces of which 

 it is composed are called Petals. When it appears to consist of 

 one piece only, it is called Monopetalous, or in common language 

 a corolla of one petal. Corollas are seen in Fig. 87, a, 109, a, 

 110, b. 



The corolla of grasses consists of one or two pieces called 

 husks or glumes (Fig. 116, b, b.), resembling the chaff-scales. 

 There is frequently appended to them a hard elongated body 

 called the awn (Fig. 96.), which is often twisted. 



The Monopetalous Corolla (Fig. 117.) consists of two parts: 

 the tube (a.), the narrow part generally enclosed in the calyx; 

 and the limb (b.), the expanded part. The following varieties of 

 this kind of corolla may be mentioned. 



Strap-shaped, narrow and flat, unless at the base. 



Tubular (Fig. 118.), consisting of a single piece, hollow and 

 of nearly equal thickness ; this term, however, is used with great 

 latitude, and, in the compound flowers, applies to corollas of 

 various forms. 



Spherical or Globose (Fig. 119.), narrow above and below 

 and enlarged in the middle. 



Bell-shaped (Fig. 120.), having the form of a bell, with the 

 margin bent back. 



Cup-shaped (Fig. 121.), of nearly the same form, with the 

 margin straight. 



Funnel-shaped (Fig. 122.), inversely conical. 



Salver-shaped (Fig. 117.), when the tube is cylindrical, but 

 very long, and the limb expanded. 



Wheel-shaped, the same as salver-shaped, with the tube very 

 short. 



Ringent or Gaping (Fig. 123. ), when the limb is divided into 

 two parts, the upper more or less arched, the under oblong; these 

 parts are called lips. 



Personate or Masked (Fig. 124.), when the limb is divided 

 into two parts, which are closely pressed together, the throat 

 ^3 eing thus closed. 



