Trunks and Props. 201 



upon the corolla, as in Solanum Hystrix ; their most usual place 

 is upon the stem, as in the Rose. Fig. 5, A, simple prickles ; 

 B, triple prickles. In some cases the petiole of a compound 

 leaf is elongated, branched, and endowed with a power of twist- 

 ing around any small body that is near it, as in the pea and many 

 others; it is then called a cirrhus or tendril. It is one of 

 the contrivances employed by nature to enable plants to sup- 

 port themselves upon others that are stronger, and has generally, 

 even by very recent writers, been spoken of as a peculiar 

 organ ; but as it is manifestly in most cases a particular form of 

 the petiole, we see no reason for regarding it in any other light. 

 At the base of the petiole on each side, is frequently seated a 

 small appendage most commonly of a texture less firm than the 

 petiole and having a sub-awled shape termination. These two 

 appendages are called Stipule, and considered by many bota- 

 nists accessory leaves. Glands are elevated spaces in the layers 

 of parenchyma, lying immediately below the cuticle or vegeta- 

 ble skin in which they cause projections ; they are of various 

 kinds and used for the secretion of different matters, salts, essen- 

 tial oils, &c. Fig. A. a tendril, c, stipulnc, with concave glands 

 on the leaf. Fig. glands on stalks. Fig. 3, A, a Bractea dif- 

 fering from the leaves ; B. the leaves. Fig. 6 shows merely a 

 handsomely arranged form of opposite leaves. Some examples 

 of the various kinds of trunks we have given in our plate. Fig. 

 7, a Squamose stem ; scaly, covered with imbricate scales. 

 Fig. 8, a voluble stem ; twining, ascending spirally, winding to 

 the right or left. Fig. 9, a Frons ; a species of trunk composed 

 of the branches and leaves blended together, are frequently 

 united with the fructification, belong properly to the Palms — and 

 Felices. Fig. 10, a Scapus, or stalk, a universal trunk raising 

 the fructification, but not the leaves, as in Narcissus and Pyrola. 

 Fig. 11, an Articulate stem, jointed ; when it is connected by 

 various joints. Fig. 12, a Diciioaiatous stem, forked ; when the 

 division is always in two parts. Fig. 13, a Brachiate stem, 

 armed; when the branches are opposite and each pair is crossed 

 by the pair next above or below it. 



Nature is as careful to preserve the trunks of vegetables from 

 excessive heat and cold as she is of animals. In cold climates 

 these trunks are covered with a warm coat of moss which an- 

 swers the purpose of fur to the bear, in preserving it from the 



