ON STIPULES 31 



Where stipules are present the leaf has two, one on 

 each side. Sometimes, however, the two stipules are 

 connate, i.e., have grown together. This may take place- 

 on the outside of the leaf, and be either confined to the 

 base, as in a Chinese Astragalus (Astragalus chinensis), 

 (figs. 39, 40), or continue for the greater part of their 

 length, as in Hedysarum esculentum (figs. 41, 42), where 



FIG. 41. FIG. 42 



HEDYSAKUM ESCULENTUM. Nat. size. 



FlG. 41. Apex of growing shoot, showing side view of stipules ; I/', youngest, 

 partly expanded leaf, with the lowest pair of leaflets still folded, and the sti- 

 pules, st', connate opposite the leaf-base ; L", next younger leaf pushing out of 

 the bud with its stipules, st". 



FIG. 42. The same showing the dorsal aspect of the connate stipules, si'. 



they are reddish brown and membranous, and develop 

 early, so that the leaves at this stage lie between two 

 rows of stipules. In Sainfoin (Onobrychis sativa) (figs. 

 43, 44) also the stipules are united for the greater part 

 of their length. In other species they are ' intrapetiolar,' 

 more or less connate on the axillary side of the leaf, as in 

 the Pondweed (Potamogeton) (fig. 45) and in the Knot- 

 weeds (Polygonum) (fig. 46), where they form the sheath, 

 called technically an ocrea. 



