128 



PARTS OF THE FLOWER 



204. Gamosepalous 

 and gamopetalous 

 flowers of sweet 

 potato. 



leaf is a sepal. If it is of one piece, it may be lobed or di- 

 vided, in which case the divisions are called calyx-lobes. In 

 like manner, the corolla may be 

 composed of petals, or it may be 

 of one piece and variously lobed. 



267. A calyx of one piece (as in 

 Fig. 204),. no matter how deeply 

 lobed, is gamosepalous. A corolla 

 of one piece is gamopetalous. When 

 these series are of separate pieces 

 (as in Fig. 202), the flower is said 

 to be polysepalous and polypelalous. 

 Sometimes both series are of sep- 

 arate parts, and sometimes only 

 one of them is so formed. The 

 floral envelopes are homologous 

 with leaves. 



268. Sepals and petals, at least when more than three or 

 five, are each in more than one whorl, and one whorl stands 

 below another so that the parts over- 

 lap. They are borne on the expanded 

 or thickened end of the flower-stalk: 

 this end is the torus. In Fig. 202 all 

 the parts are seen as attached to the 

 torus. This part is sometimes called 

 a receptacle, but this word is a com- 

 mon-language term of several mean- 

 ings, whereas torus is a technical word 

 exclusively. Sometimes one part is 

 attached to another part, as in the 

 fuchsia (Fig. 205) in which the petals 

 are borne on the calyx-tube. 



269. Essential Organs.— The 

 essential organs are borne within 

 the floral envelopes (when envelopes 



205. Flower of fuchsia 

 in section. 



