MOVEMENTS AND ATTITUDES OF PLANTS 151 



studied. Each leaf is pinnate, i. e. with leaflets arranged 

 on each side of the midrib like the pinnae of a feather. 



Fig. 99. Wood Sorrel. a, young leaves as they first open; 

 b, day-position of leaflets ; c, night-position ; d, bases of leaflets 

 enlarged ; e, f, g, movements of growing flower-stalk ; h, bulbils 

 in the axils of leaves ; *, vertical section of a bulbil ; m, motile 

 organs ; r, rhizome. 



A leaf of the False Acacia, like most pinnate leaves, ends 

 in a single leaflet. At the base of the leaf are two stipules 

 transformed into spines. During the day the leaflets are 

 horizontal, but in intense sunlight they move upwards, 



