ON THE FORMS OF STIPULES 161 



pinnatipartite, as in Viola tricolor (fig. 27), 

 Passiflora pinnatistipula, and Pomaria glandulosa ; or 

 palmatipartite, as in Althcea rosea, A. ficifolia, Ptero- 

 spermwn acerifolium, &c. 



In texture they may be foliaceous, as in the Hearts- 

 ease ; membranous, when thin, flexible, and almost trans- 

 parent ; scarious, when dry and coriaceous, as generally 

 in the Beech and Hornbeam; spinous, as in Robinia 

 (fig. 34) ; cirrhose, when produced into tendrils, as 

 iri Smilax. 



In many cases the stipules are very small, sometimes 

 quite minute, as in Hymenanthera (fig. 28), a plant 

 belonging to the Violet family. The Holly is described 

 in Bentham and Hooker's l Genera Plantarum ' as exstip- 

 ulate, but (fig. 29) there are minute black points at the 

 base of the leaves, which appear to represent stipules. 

 In others they are very large, as in the common Pea 

 (Pisum sativum) (fig: 26), Lathyrus maritimus (fig. 296), 

 and Bucklandia (fig. 190). 



Many plants have stipules of different forms. 



The stipules covering winter-buds are often different 

 in form from those of the subsequent leaves (see, for 

 instance, figs. 215-235). 



Where stipules serve as bud-scales there is generally 

 a series of different forms, from those of the outer 

 scale to those of the ordinary leaf. 



In the Thorn (Cratcegus Oxyaoantha) (fig. 286) the 

 stipules on the leaves of the short lateral spurs and those 



M 



