38 BUDS AND STIPULES 



always more or less connate and sheathing, or the 

 petioles are widened so as to protect the bud. 



Again, the Guttiferce have broad petioles and no 

 stipules. Quiina, however, is an exception, for it has 

 stipules, and here also the petiole is narrowed at the 

 base. 



FIG. 50. CISTUS VAGINATUS. Nat. size. 



a a axis ; Z, portion of leaf ; sh, sheath formed by the dilated and coimate 

 bases of the petioles ; ab, ab, axillary buds. 



The Rosacece generally have stipules, but in Exo- 

 chorda some species are exstipulate. In Exochorda 

 Alberti (figs. 53, 54). for instance, the leaves have well- 

 developed foliaceous stipules. 



On the other ~hand,Exochorda grandiflora (figs. 51, 52) 

 is exstipulate. The petiole, however, is concave and am- 

 plexicaul, and the winter-bud is covered with a number 

 of broadly triangular brown scales, some of which show 



