60 



STEMS AND STALKS. 



Fig, 22. 



3d. Scape, (Fig. 22, a, a,) a 

 stalk springing from the root, wlych 

 bears the flower and fruit, but not 

 the leaves ; as the Dandelion, the 

 Cowslip, and the Lily of the Val- 

 ley. Plants with scapes are some- 

 times called stemless plants ; in this 

 case, the scape would be consider- 

 ed as a peduncle proceeding from 

 the root. 



4th. Peduncle, or flower stalk, is but a subdivision of the 

 caulis or stem, (See Fig. 20, b,) ; it bears the flower and fruit, 

 but not the leaves ; when the peduncle is divided, each subdi- 

 vision is called a pedicel.* 



The peduncle, or flower stalk, is, 



Cavline, when it grows immediately out of the main stem ; 

 Rameous, or branching, when it grows out of a main branch ; 

 Axillary, growing between a leaf and stem, or between a branch and stem; 

 Terminal, when it terminates a stem or branch ; 

 Lateral, when situated on the side of a stem or branch ; 

 . Uni-Jlora, bearing one flower ; bi-flora, two flowers ; tri-flora, three flowers ; 

 Multi-flora, bearing many flowers. 



When there is no peduncle or flower stalk, the flowers are 

 said to be sessile. 



5th. Petiole, or leaf stalk, is a kind of stem, like a fulcrum, 

 supporting the leaf (See Fig. 20, a,) ; it is usually green, and 

 appears to be a part of the leaf itself. The petiole of many 

 plants is somewhat in the form of a cylinder ; but the upper sur- 

 face is rather flattened, the under surface convex. You will 

 find this remark useful, in distinguishing the foot-stalks of com- 

 pound leaves, from young branches, with which they are some- 

 times confounded. In most cases, the leaves and flowers are 

 supported by distinct foot-stalks, but sometimes the foot-stalk 

 supports both the leaf and flower. 



The petiole may be, 



Terete, round, as in the Holly-hock ; 



Semi-Terete, half round, as in the Yellow water-lily ; 



Compressed, flattened, as the Poplar ; 



Alated, winged, or furnished on each side with a leafy appendage ; 



Cirriferus, having tendrils, as the Pea ; 



Climbing, performing the office of a tendril, as the CLEMATIS virginica. 



The Petiole is often compared with the leaf, as the peduncle 

 is with the flower, with regard to their relative length. 



* In determining the species of plants, we often consider the length of the pe- 

 duncle, compared with the flower : as whether the peduncles are longer or 

 shorter than the flower. 



Scape Peduncle Petiole. 



