GENEBAL MOEPHOLOaY OF THE PLANT 55 



modifications as regards venation, apex, incision, outline, 

 margins, surface, &c. The stipules are often wanting, and the 

 leaves are then said to be exstipulate ; when present, the leaves 

 are stipulate. They are often overlooked from their small 

 size ; sometimes, however, they are very large, as in the Pansy 

 (fig. 83), and in the common Pea (fig- 84). In the leaves of 

 Lathyrus Aphaca (fig. 186) the axis of the phyllopodmm does 



Fig. 83. 



Fia 83 Petiolate leaf of PaBsy ( Twla tricolor) witla large caulinary stipules 



at its base Fig. 84. A portion of the flowering stem of the common 



Pea with a pinnate leaf terminated by a tendril, and having two large 

 stipules at its base, the lower margins of which are dentate. 



not become winged, but the stipules, s, i, are here very large 

 and perform all the functions discharged usually by the leaf-blade. 



Stipules either remain attached as long as the lamina, 

 when they are said to be persistent ; or they fall off soon after 

 its expansion, in which case they are deciduous. In the Beech, 

 the Fig, tbe MagnoUa, &c., they form the tegmenta or protective 

 coverings of the buds, and fall off as these open. 



The stipules vary in their position with regard to the petiole 



